What do we have to believe about the traits of Jesus Himself (God, sinless, etc.) for our belief and trust in his atonement to be valid. For example, how could His death on the cross pay for our sins if He was not the perfect Son of God?
At the dawn of history, when God wanted the perfect symbol of the Redeemer who would come to die for the sins of the people, He chose a lamb without any blemish or defect to be the sin offering. A little lamb is the picture of innocence and a lamb without defect is the perfect picture. It was no accident that when John the Baptist saw Jesus coming toward him he said, “Look, the Lamb of God who takes away the sin of the world” (John 1:29).
From a theological standpoint if Jesus was not a perfect, sinless man then He could not have qualified to be our redeemer. That means He had to be God in human form, because there are no sinless men. In my opinion those who don’t believe in His deity are at the very least on shaky ground, even if they believe He died for their sins, because if He isn’t God He not only couldn’t die for our sins, someone would have to have died for His.
For you know that it was not with perishable things such as silver or gold that you were redeemed from the empty way of life handed down to you from your ancestors, but with the precious blood of Christ, a lamb without blemish or defect. He was chosen before the creation of the world, but was revealed in these last times for your sake. Through him you believe in God, who raised him from the dead and glorified him, and so your faith and hope are in God (1 Peter 1:18-21).