How do we know that confession is essential for salvation?

Romans 10:9-10 elaborates on the relationship between confession and salvation: 'If thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved.' Here, confession is highlighted not as a prerequisite action to earn salvation, but as a natural expression of belief. It is through the heart that one believes unto righteousness, and with the mouth, one makes a confession unto salvation. This understanding aligns with the doctrine of sovereign grace, where belief is granted to the elect, enabling them to confess authentically. Thus, true confession arises from a heart touched by God's grace.