What does the Bible say about confirmation in Christ?

In 1 Corinthians 1:6-8, Paul asserts that the testimony of Christ is confirmed in believers, illustrating that true faith is a result of God's sovereign grace. This confirmation is not dependent on our actions but is rooted in God's faithfulness and the completed work of Christ. It emphasizes that those who are truly of Christ will be kept by His power and will not fall away. Thus, the confirmation in Christ assures believers that their salvation is secure not because of their own efforts, but because of Christ's obedience unto death and the grace of God that sustains them.