What does the Bible say about the security of God's sheep?

The security of God's sheep is a profound theme in Scripture, particularly found in John 10:27-28, where Jesus declares, 'My sheep hear my voice, and I know them, and they follow me. And I give unto them eternal life, and they shall never perish, neither shall any man pluck them out of my hand.' This means that true believers, referred to as God's sheep, have the assurance of salvation and cannot be taken away from Christ's protection. This doctrine emphasizes God's sovereign grace, affirming that salvation is a gift and not dependent on human effort, highlighting the eternal safety that comes from being in Christ.