Nick Batzig explains for Reformation 21.
While the human nature of Jesus was inseparably united to the Divine nature of the second Person of the Godhead, Jesus needed to live a perfectly sinless life in the power and by the grace of the Holy Spirit. It was not sufficient for Him–as the second Adam and representative of a new humanity–to merely live according to His Divine nature. What we need as fallen men is a human Redeemer who would gain a human holiness for His people and would die a human death in their place
