How do we know that Jesus's sacrifice is sufficient for salvation?

The sufficiency of Jesus's sacrifice is rooted in His flawless obedience and substitutionary atonement. According to Romans 8:3-4, God sent His own Son in the likeness of sinful flesh to condemn sin in the flesh, so that the righteous requirements of the law might be fully met in us. Christ bore the wrath of God in our place, which is reinforced in 1 John 4:10, where it states that God sent His Son to be the propitiation for our sins. This assures believers that Christ’s sacrifice is complete and perfect, leaving nothing lacking for our salvation.