First Sunday of Advent, Year A: Isaiah 2:1-5, Romans 13:11-14, Matthew 24:37-44.
This Sunday presents a group of readings that speak to the essential character of Advent. The theme, of course, is preparation for God’s coming. As we are taught, this coming is something that happens in the stream of time (Christ’s coming into humanity) as well as something greater that ends the world as we know it. Advent invites us to again celebrate the great coming has already happened and also to prepare ourselves for the final coming that has yet to happen.
What strikes me in these readings is the fully active nature of the preparing we are called to do. This isn’t a “sit still and wait patiently” moment like those I was trained to endure as a child. Nor is it a frantic “get the house ready before the guests arrive” type of preparation. Instead, it’s a renewal of the call that Jesus puts in our hearts throughout his ministry – a reminder that he has given us the Way to think, love, behave, and pray. This is what makes Christianity not just a good theological or moral system; it is meant to be lived out actively here and now because, as Jesus promises us, “at an hour you do not expect, the Son of Man will come.”
Let’s first consider Isaiah’s prophecy. Isaiah, being given the vision of Christ’s entry into humanity, struggles to explain this heavenly plan (as any human would), employing both prophetic and poetic language. Just imagine if God gave you the vision of divinity’s supernova explosion into humanity. How would that knowledge manifest itself in your imagination? Isaiah says that “the mountain of the LORD’s house shall be established as the highest mountain.” This is an interesting doubling of prophetic and symbolic language. First, mountains have great meaning in scripture: they symbolize the nearness of God, God’s protection, and the act of worship. Second, Isaiah adds “of the LORD’s house,” which is sung in the Psalms as the dreamed-of resting place for the righteous (i.e., heaven). It is also seen in earthly terms as the temple built by Solomon in Jerusalem, physically housing the Ark of the Covenant in the Holy of Holies. In both senses, the “house” is where God, in His glory and majesty, is found. So, when Isaiah calls this the “mountain of the LORD’s house,” there’s a bit of emphasis going on, like “the oceanic center of the ocean.” This mountain is the place where the very heart of the divine person of God can be found. Interestingly, he says that this “will be established as the highest mountain.” A devout Jewish prophet would already think of God as the “highest mountain,” so what can he mean by this action of “being established”? This isn’t a theological statement about the order of things – it’s a statement about something happening, about humanity realizing who God is in a new way. I understand this as Isaiah prophesying the Christ Event. By that, I mean the Incarnation, Jesus’s ministry, the Passion, Crucifixion, Resurrection, establishment of the Church, and Ascension to heaven. This is how He is “established as the highest mountain.”
Some Famous Mountains in Scripture
- Mt. Moriah – where Abraham was to sacrifice Isaac and where Solomon built God’s temple
- Mt. Sinai – Moses meets God, receives the 10 commandments
- Mt. Ararat – Noah’s ark is deposited by God
- Mt. Zion – captured by David and becomes the site of Jerusalem (its temple considered the “Lord’s house”)
- Mt. Carmel – Where Elijah challenged the prophets of Baal.
- Mt. Tabor – Jesus is transfigured
- Mount of Olives – Jesus prays before his Passion and Crucifixion
Isaiah shares that “All nations shall stream toward it,” as indeed thousands were baptized in the Spirit the day of Pentecost and ever since, over the centuries. Importantly, people go to this “mountain” that is Christ in order to learn how to live correctly: “that he may instruct us in his ways, and we may walk in his paths.” Here in 740 BC we hear Isaiah giving us a kernel of truly Christian teaching! We don’t go to Christ in order to passively sit and bask in his presence (although we can do this during Adoration). We aren’t a religion where our highest experience is a letting go of the world and reality, like Buddhist nirvana. No, just as God cared about His creation so much that He sent Jesus to be with us, we are called to care about His creation and “walk in his paths.” The point of meeting God on His mountain is so that we can learn to live rightly in the world He has given us, not so that we can abandon the world. And what does this meeting with Christ give us? Isaiah prophetically tells us that it is to love one another fully (just as Jesus will teach nearly 800 years later). Isaiah speaks of this love as the reign of peace, when people will “beat their swords into plowshares” and “one nation shall not raise the sword against another.” As Isaiah sees, Christ makes the Kingdom of God a reality for us, here and now. The Kingdom is marked by peace and love.
Once Isaiah receives this vision, there is nothing greater to hope for than the Kingdom made available to us. Thus, Isaiah’s passage ends with the exhortation, “let us walk in the light of the Lord!” This is exactly where we are in Advent. We are reminded of the great coming of the Lord and urged to follow the Way he has provided, to “walk in the light.”
St. Paul takes up this same message, with the same realization that Isaiah received. I love the domestic simplicity of his words: “it is the hour now for you to awake from sleep. For our salvation is nearer now than when we first believed.” Paul is rousting us from our sleep, kicking the bed frame, pulling off the sheets. “The night is advanced,” he writes, “the day is at hand.” This whirlwind of motion and action continues: “Let us then throw off the works of darkness and put on the armor of light; let us conduct ourselves properly as in the day.” He paints a picture of lively action and – importantly – light. He contrasts the light of day with the dark acts of night. Light is central to both Isaiah and Paul. This imagery if very familiar to us, its meaning seemingly obvious, but do we really understand what it means to “walk in the light” and “put on the armor of light”?
On the most mundane level, light allows us to see things clearly. Things in the light are exposed for all to see – given time to examine them, we can notice the smallest of details. Walking in the light, then, means first to allow ourselves to be seen and not hiding from scrutiny or observance.
But light isn’t just a neutral source of illumination. As we know from our founding story of Genesis, light comes specifically from the Creator: “God said, ‘Let there be light’; and there was light. And God saw that the light was good” (Gen 1:3-4a). Light, understood within our belief system, thus also has a moral significance. If God created it AND called it good, then it is good! So, while light promotes understanding (c.f., “The unfolding of your words gives light; it imparts understanding to the simple,” Ps 119:130), this is an understanding that is good, upright, morally correct. Now we are getting deeper. To “walk in the light” means that we live in a way that is open to scrutiny but also a way that imparts moral understanding to those around us. This is why we hear in Proverbs, “the path of the righteous is like the light of dawn, that shines brighter and brighter until the full day” (Pro 4:18).
A final level of meaning attached to light is theological. Everything we have said about light culminates in the figure of Jesus Christ: he is the understanding, the Logos, of God that has come to illuminate the moral way for humanity. As he himself says, “I am the Light of the world; he who follows Me will not walk in the darkness, but will have the Light of life” (Jn 8:12). If the second person of the Trinity is Light itself (and, closely related, Wisdom and Truth), then his redemptive work on earth is to bring us into his light, which provides a path to eternal life with the Father. He didn’t come just to be a light and then retreat off into heaven – he calls us adopted brothers and sisters and thus sons and daughters of the Father. Our baptism in water and the Spirit cleanse us and initiate us, while the other sacraments help to feed us and keep us in the light that is Christ. This is exactly what St. Paul is saying in today’s reading and what he writes elsewhere, for instance, to the Ephesians: “for you were formerly darkness, but now you are Light in the Lord; walk as children of Light” (Eph 5:8). Living in Christ as the Light of the world — “putting on” Christ — is essentially transformative.
So, with this mini examination of “light” under our belts, let’s look again at Paul’s words: “put on the armor of light … put on the Lord Jesus Christ.” Paul is dedicated to this analogy of armoring ourselves with the power of God. We can turn again to his letter to the Ephesians where he describes it in detail:
Put on the whole armor of God, so that you may be able to stand against the wiles of the devil. For our struggle is not against enemies of blood and flesh, but against the rulers, against the authorities, against the cosmic powers of this present darkness, against the spiritual forces of evil in the heavenly places. Therefore take up the whole armor of God, so that you may be able to withstand on that evil day, and having done everything, to stand firm. Stand therefore, and fasten the belt of truth around your waist, and put on the breastplate of righteousness. As shoes for your feet put on whatever will make you ready to proclaim the gospel of peace. With all of these, take the shield of faith, with which you will be able to quench all the flaming arrows of the evil one. Take the helmet of salvation, and the sword of the Spirit, which is the word of God (Eph 6:11-17).
Paul reminds us of the spiritual world in which we live, invisible to our eyes but real nonetheless. He depicts this as the battleground that really matters. To modern ears, this might sound archaic and superstitious. But we must realize that Paul is describing the same things we encounter today, just in a manner of understanding that “moderns” no longer use. In both ages, we might see a person who seeks profit out of every situation to the extent of openly cheating others. People in Paul’s age would describe them as being under the influence of evil spirits or the devil. We just call them selfish. More close to home, we might be tempted to shout at the person who cuts us off in traffic, to make fun of someone, to lie about something small, etc. What makes us act in these ways, with no charity in our hearts, no light in our actions? What else but “the spiritual forces of evil”? They tempt us to commit venial sins and walk in darkness. The armor of light is spiritual armor to protect us from “the cosmic powers of this present darkness.”
Paul assures us that we can trust this armor of light to help us live without sin. When we “put on” Christ, we can do so joyfully, for we know our Savior has already beaten death and Satan, and with him in our hearts, there is nothing we cannot do.
But I ask myself: isn’t this what we’re supposed to be doing all the time? Isn’t this what it means to be Christian? And the answer is yes. Yet this season of Advent puts special attention on walking in the light. Why?
The answer comes from the mouth of our Savior. “you do not know on which day your Lord will come,” he says in the gospel reading, and like the master of the house not knowing when the thief comes, “you also must be prepared, for at an hour you do not expect, the Son of Man will come.” What a tension we live with! Something momentous hangs over us: a moment of ending, judgment, and new beginning. The stakes are so much higher than simple death; we are talking about eternal damnation or eternal glory. Let’s say that again: eternal.
There are a few ways we can react to this: 1. rejection. This path can only be taken by willfully turning our back on God and His Word. What we know of hell is that it is precisely this willful rejection of God. If we’re this far down the road to even be considering Jesus’s words, we have accepted a certain relationship to our Creator, and rejection of his teaching of judgment simply means we reject Him and have placed ourselves in hell.
The second reaction is anxiety and fear. This is a normal, rational reaction to having something momentous hanging over us. Rational because we know that we do not deserve heaven, and frankly we can never earn it. But this is not a particularly spiritual or faithful reaction. What do we know of our God? Over and over in scriptures we hear of His great mercy. We learn that He yearns for us to be with Him in the Kingdom. And we have proof of this in His Son, who He sent to us so that we can have a Way to heaven. Only a loving God would give His son as a sacrifice for our unworthiness. This is His great sign that He will provide the grace, mercy, and love to bring us to Him. Our half of the covenant is that we promise to walk in the light.
So all of this leads us quite naturally and logically to the third reaction: hope and joy. Jesus reassures us: “Do not be afraid, little flock, for it is your Father’s good pleasure to give you the kingdom” (Luke 12:32). What a simple and awesome message! Like today’s gospel of Matthew, Luke’s gospel quickly follows these words with the thief analogy: “You also must be ready, for the Son of Man is coming at an unexpected hour” (Luke 12:40). This pairing of confidence in the Father’s mercy with a warning for preparedness is a necessary component of our Christian worldview. Our human nature coupled with the constant spiritual barrage of temptation creates a situation where we slip into sin. If we had overwhelming confidence in God’s mercy without a warning for preparedness, we would be tempted to just wait to repent until things got really bad (or on our deathbed). It is critical that we remain spiritually upright because the judgment will come without warning. This is the eschatological reason that Christians act the way we do.
Doing good because we want the reward of heaven is a bit of a simplistic understanding, however. The deeper reason is wrapped up in who God is: pure light, life, goodness, truth, wisdom, beauty, and love. We crave final union with this pure divinity, and we learn to walk in the ways of light, goodness, and truth while here on earth because we love all that He is. We follow His law (perfected in Christ) because we don’t want to offend the One most deserving of all our love and because we trust that He gives us His law for our own benefit. The deeper reason Christians act the way we do is all about conforming our hearts to our God.
With so much at stake (eternity) and with the goal of conforming our hearts to God and His law, we must open ourselves to a real examination. Is walking in the light and being prepared only about avoiding sin and doing good deeds? It must be more than that. If we walk in the spiritual light, preparing for final union with God, the goal is to become as much like Christ as we can so that union is possible. Trying to fuse dirty iron with pure gold is not the scenario we want. So, ask yourself the hard questions: do I prioritize the “right” of a person to choose what happens with their body knowing the outcome may be aborted children, even if I claim that I am personally pro-life? Here’s another: do I support the “right” for people to carry weapons of death, perhaps even carrying my own out of fear? Does God call us to protect our lives at all costs or does He instead say, “There is no greater love than to lay down one’s life for one’s friends”? As we start to examine “hot button” topics, American Catholics tend to find that their heart is steered more by their political convictions than by God’s teaching. But God’s teachings aren’t there to make us feel good about our political party affiliations. And the opposite is certainly untrue as well. Really, truly walking in the light means conforming all of our heart to God and His teaching of righteousness. So, a third question: while maintaining the teachings of the Church, do I treat transgender and gay people, illegal immigrants, the homeless, and sinners of all stripes with love and respect, equal to me as a child of God, even if I believe that their choices and lifestyles are against God? So often we mistakenly judge others based on moral teachings we are trying to live up to. We have only one rule about how to act with others: love your neighbor as yourself. Putting on Christ and living in the light also means not judging, but loving. If this is uncomfortable, well, good! Because the stakes are high.
Back to the thrust of today’s readings, let’s remember that the spirit of Advent is active preparedness – one of both deeds and conversion of heart. I particularly like Luke’s companion gospel to today’s passage from Matthew: “Be dressed for action and have your lamps lit; be like those who are waiting for their master to return from the wedding banquet, so that they may open the door for him as soon as he comes and knocks” (Luke 12:35-36). We are “dressed for action” in our armor of light. The lamps are lit with God’s wisdom so that we can see the Way. And we understand ourselves as humble servants of our great master, who is returning for us on the Day of Judgment. What a great vision, and may we all live up to it!
Great post, Michael! Thank you for sharing such profound insight. Beautiful is your explanation of what it means to walk in light. Namely, to “live in a way that is open to scrutiny but also a way that imparts moral understanding to those around us.” Also, I love the deeply profound questions at the end of the article that call the reader into what I would say is an urgent and personal examination of conscience. An examination in which one must reconcile within themself some of the most pressing and urgent issues of today. What does it really mean to “walk in the light,” specifically as it relates to our own positions and actions in relation to Catholic social teaching and The Beatitudes? Of all folks, it was Alex Trebek that profoundly stated “don’t tell me what you believe in. I’ll observe how you behave and I’ll make my own determination.”