The Bible says that everyone who believes in Jesus Christ is born of God and thus can know they are saved (1 John 5:1).
In 1 John 5:1, it clearly states that 'Whosoever believeth that Jesus is the Christ is born of God.' This is the foundation for assurance of salvation. When one genuinely believes in Christ, this faith is the evidence of their new birth. Further, 1 John 5:3 adds that love for God is evidenced by keeping His commandments. If a believer exhibits love for God and seeks to obey Him, this affirms their salvation. Therefore, the assurance of salvation comes through faith in Christ and the resulting transformation in one's life as a response to that faith.
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