How do we know that Christ's sacrifice was sufficient for us?

The sufficiency of Christ's sacrifice is rooted in the doctrine of particular redemption, which asserts that Jesus died specifically for those whom the Father had chosen. Ephesians 1 explains that God has blessed us with every spiritual blessing in Christ, which signifies His foreknowledge and preordination of our salvation. This promise is highlighted in Romans 8, where it states that whom God foreknew, He predestined, called, justified, and glorified. Therefore, our confidence in the sufficiency of Christ's atonement rests not only on His death and resurrection but also on the unchangeable nature of God’s purposes—guaranteeing that all for whom Christ died will surely be saved.