The word atonement in English is literally “at-one-ment”.  Theories that make the atonement a mere legal transaction because of the cross miss its fuller and richer meanings.  The idea is that God and man are reconciled.  When we are at-one with Jesus, being baptized into Him, in solidarity with Him, we are at-one with the Father through our Mediator.  When we are at-one with Jesus, we have found the Way to the Father.  But the final part of this at-one-ment is that we are so at-one with Him that we have become like Him.  Entering into divine likeness is the end to which at-one-ment moves.  We must not cut short this work.

“God was in Christ reconciling the world to Himself,…so that we might become the righteousness of God in Him.” 2 Corinthians 5:19, 21 (NASB)