What does the Bible say about once saved always saved?

The doctrine of 'once saved, always saved' emphasizes the permanence of salvation for those truly in Christ. Jesus assures us that those who are genuinely saved will persevere in faith due to the life and faith granted by Him. However, the Scriptures also provide numerous warnings to believers, urging them to remain steadfast and to avoid the pitfalls of unbelief, neglect, and apathy towards their relationship with God. Abiding in Christ reflects the true evidence of one's salvation and the necessity of spiritual fruitfulness in a believer's life.

In John 15, Jesus illustrates this principle with the analogy of the vine and branches, indicating that true disciples, those who are genuinely united with Him, will produce fruit as a natural outflow of their relationship with the Savior. Hence, what is essential for Christians is understanding that while salvation is eternally secure, the fruitfulness and perseverance in faith are indicators of that saving grace manifesting in their lives.