Romans 5:10
For if, when we were God's enemies, we were reconciled to him through the death of his Son, much more, now that we have become reconciled, shall we be saved by virtue of Christ's Life.
2 Corinthians 5:18-21
But all this is the work of God, who reconciled us to himself through Christ, and gave us the Ministry of Reconciliation--
Ephesians 2:16
And when, upon the cross, he had destroyed their mutual enmity, he sought by means of his cross to reconcile them both to God, united in one Body.
Colossians 1:21-22
And it pleased God that you, once estranged from him and hostile towards him in your thoughts, intent only on wickedness--
Hebrews 2:17
And consequently it was necessary that he should in all points be made like 'his Brothers,' in order that he might prove a merciful as well as a faithful High Priest in man's relations with God, for the purpose of expiating the sins of his People.
Hebrews 9:18-23
This explains why even the first Covenant was not ratified without the shedding of blood.