But the just shall live by his faith.
Another verse repeated several times showing the importance of faith.
For I am not ashamed of the gospel of Christ, for it is the power of God to salvation for everyone who believes, for the Jew first and also for the Greek. For in it the righteousness of God is revealed from faith to faith; as it is written, “The just shall live by faith.”
But that no one is justified by the law in the sight of God is evident, for “the just shall live by faith.” Yet the law is not of faith, but “the man who does them shall live by them.”
For you have need of endurance, so that after you have done the will of God, you may receive the promise: “For yet a little while, and He who is coming will come and will not tarry. Now the just shall live by faith; but if anyone draws back, My soul has no pleasure in him.” But we are not of those who draw back to perdition, but of those who believe to the saving of the soul.
These verses show the importance for you, the believer, to live with complete trust in God. It’s not always easy as your adversary tosses obstacles in your way in an attempt to cause you to stumble in your faith-walk.
Your faith is not for you alone but for those around you. When you righteously live by faith then others see your good works in Christ and, perhaps, give their heart to Him.