What did Paul mean when he wrote 'to live is Christ' (Philippians 1:21)?

TL;DR:

A Christian will have difficulties, but Christ brings joy through these difficulties. True life is found in living for Christ.

In Philippians 1:21, Paul says the focus of all he does is glorifying Jesus and making Him known. Many of Paul’s epistles record a life bound up in Jesus—imitating Him, preaching Him, obeying Him, and making disciples of Him (1 Corinthians 2:2). His letters relate his joy, even amid the hardship and suffering he endured, for the sake of proclaiming Christ to others (Philippians 3:8–11). Prioritizing the Lord isn’t just a New Testament teaching, though. In Genesis, Abraham’s willingness to sacrifice Isaac showed that God was the center of his life (Genesis 22:10–12). The first of the Ten Commandments, which is foundational to the Mosaic covenant, is the command to put no other gods before the true God (Exodus 20:3).The Mosaic law contained the shema, a prayer Jews traditionally said daily. That prayer included the command to love the Lord with all of our heart, mind, and strength (Deuteronomy 6:4–9). The entire Bible emphasizes that the Lord should be the center of our lives. May we, with Paul, be able to declare "to live is Christ" (Philippians 1:21).

from the old testament

Genesis 22:10–12 records Abraham’s faithfulness to God: “Then Abraham reached out his hand and took the knife to slaughter his son. But the angel of the Lord called to him from heaven and said, ‘Abraham, Abraham!’ And he said, ‘Here I am.’ He said, ‘Do not lay your hand on the boy or do anything to him, for now I know that you fear God, seeing you have not withheld your son, your only son, from me.’” Abraham truly lived for God because he was willing to give up what meant most to him in life: his son. Abraham trusted God enough to know He would fulfill His promises to make a great nation of him.
Exodus 20:3 showed the ancient Jews that God should be first in their lives: “You shall have no other gods before me.” For ancient cultures, having other gods usually meant idols made of wood and stone. In the modern day, it often means material wealth or personal pursuits that we prioritize over our love for God.
Ancient Israelites were to put God first in their lives, as expressed in Deuteronomy 6:5–7: “You shall love the Lord your God with all your heart and with all your soul and with all your might. And these words that I command you today shall be on your heart. You shall teach them diligently to your children, and shall talk of them when you sit in your house, and when you walk by the way, and when you lie down, and when you rise.” Their lives were to revolve around love and devotion to the Lord, just as ours also should today.

from the new testament

Paul's statement in Philippians 1:21, taken in its entirety, sums up his approach to life and death: “For to me to live is Christ, and to die is gain.” Paul declares that the focus, the reason, for everything he does is to glorify Jesus and make Him known (Philippians 1:20).
In Matthew 19:21–22, Jesus showed a rich young man what the priority in his life was: “Jesus said to him, ‘If you would be perfect, go, sell what you possess and give to the poor, and you will have treasure in heaven; and come, follow me.’ When the young man heard this he went away sorrowful, for he had great possessions.” Sometimes, we think we’re living for God, but the Lord reveals to us that we’re putting something else before Him.
In 1 Corinthians 2:2, Paul distills his message to its core: "For I decided to know nothing among you except Jesus Christ and him crucified.” All the words of wisdom mean nothing without that truth. Christ’s death and resurrection was at the forefront of Paul’s life, and it should be the same for us.

implications for today

Beatings, shipwreck, imprisonment, scorn—experiences like those aren’t what most people would call a “good life.” But if they happen because of our devotion to the Lord, we are living the most purposeful life we could ever lead. Paul experienced those hardships and more (2 Corinthians 11:16–33), yet he was still able to tell the Philippian church to “rejoice in the Lord always” (Philippians 4:4, emphasis added). Do you center your life on Christ? Do you make time to study the Bible to know who God is and what His purpose is for us? Are you willing to withstand the scorn of this world for the glory of the next? The natural man doesn’t understand joy in the face of adversity. But believers know Christ strengthens us to live such a life (Philippians 4:13). When we live for Christ, by His power, and abiding in Him (John 15), we experience His love, grace, comfort, power and equipping for service (John 10:10; Ephesians 1:3–14; 2 Peter 1:3). He has “overcome the world” (John 16:33) and gives us the privilege of joining in His work. Have you accepted that privilege? May we, with Paul, be able to declare "to live is Christ" (Philippians 1:21).

understand

We are called to live for Christ.
True life is found in living for Christ.
Christ gives us joy in life despite difficulties.

reflect

How does "to live is Christ" influence your daily decisions and priorities?
In what areas of your life do you struggle to center your focus on Christ? How can you address those challenges?
Can you recall a specific time when you found joy in Christ during a difficult situation? What did that experience teach you?

engage

What examples in the Bible encourage us to see that “to live is Christ”?
How does Paul's commitment to living for Christ challenge or inspire us in our own walks of faith?
How should understanding that true life is found in living for Christ shape our perspective on priorities in this life?