How do we know God's people are made holy?

The holiness of God's people comes not from their adherence to the law or any good works, but solely from God's calling and sanctifying power in Christ. In Acts 10, God reveals to Peter that what He has cleansed should not be called common or unclean, illustrating that those whom God has chosen are forever holy in Him. Hebrews 10:10 affirms that we are sanctified through the offering of the body of Jesus Christ once for all, emphasizing that it's God's work that imparts holiness, granting us faith to believe as demonstrated in the stories of Cornelius and Peter.