Because God gives man eternal life through Jesus Christ, the believer is secure in salvation for eternity. Salvation is maintained by the grace and power of God, not by the self-effort of the Christian. It is the grace and keeping power of God that gives this security.

Scriptures for reference: John 10:29; 2 Timothy 1:12; 

Hebrews 7:25; 10:10,14; 1 Peter 1:3-5