What does the Bible say about the security of believers in Christ?

In John 10:27-28, Jesus assures His followers, saying, '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 affirms that the believer’s security rests entirely in Christ. He is the Great Shepherd who knows His sheep intimately, and their eternal life is a gift from Him. The idea that no one can take them from His hand, including themselves, highlights the complete and sovereign nature of salvation. It emphasizes that true security is found only in Christ’s work on behalf of His chosen people.