The believer testifies, "I know that my sins are forgiven by grace, through faith in Jesus Christ." The doubter asks, "How can I know for sure?" The Bible gives a clear answer, "The just shall live by faith."
Do you have the assurance that Christ lives in your life? Faith is the evidence. It is a faith that comes by hearing the word of God. Such faith is an abiding gift of the Holy Spirit. Doubt is dismissed, as you confess, "I live by faith in the Son of God, who loved me and gave Himself for me."
Do you have faith in God and His Son Jesus Christ? If you do, it's because of the Spirit of grace working in your heart. God's Spirit delivers you from doubt and unbelief to faith in the living God. It's a faith from Jesus Christ, the author and finisher of your faith. If you don't have such a sure faith, look unto Jesus to do in you what you cannot do for yourself. He will be the source of your faith.
"The just shall live by faith."
Habakkuk 2:4
"For by grace are you saved through faith,
and that not of yourselves;
it is the gift of God."
Ephesians 2:8
