That because of his divine nature his obedience and suffering would be perfect and effective; and also that he would be able to bear the righteous anger of God against sin and yet overcome death.
“For in Christ all the fullness of the Deity lives in bodily form, and in Christ you have been brought to fullness.” (Colossians 2:9,10)
All the fullness of the Deity
How can the death of just one human being redeem a whole world of sinners? How can just one life take the place of millions of lives? Only if that one human life is infinitely pure and holy, so that our sins are swallowed up in His righteousness like a speck of dust in the vastness of space. Only an infinitely pure and holy individual could bear the penalty of sin for the whole human race, pass through death and yet be untouched by it (Acts 2:24).
We have been brought to fullness
God did not send a third party to redeem us; He came ‘in person’. “The Word became flesh and made His dwelling among us.” (John 1:14) The Most High stooped down to our level (Psalm 113:5-8), in order to join us to Himself. “The Son of God became the Son of Man so that the sons of men might become the sons of God.”
If we have a relationship with Christ, what more could we possibly need? He shares with us His perfect righteousness, His absolute holiness, and His infinite life.
O Rising Sun,
You are the splendour of eternal light
And the sun of justice.
O come and enlighten those who sit in darkness
And in the shadow of death.
(from Celtic Daily Prayer: Advent)