What is the relationship between belief and assurance?

Belief in Jesus as the Son of God is the foundation of salvation, as seen in John 3:36. Assurance, however, can fluctuate based on circumstances or personal struggles. For example, Peter struggled with assurance despite never abandoning his belief in Christ. True faith is not rooted in the assurance of salvation but in a steadfast belief in who Christ is and what He has accomplished. Thus, while assurance is a wonderful aspect of faith, true belief sustains us even during times of doubt.