CCC 712 The characteristics of the awaited Messiah begin to appear in the “Book of Emmanuel” (“Isaiah said this when he saw his glory,”1 speaking of Christ), especially in the first two verses of Isaiah 11:
There shall come forth a shoot from the stump of Jesse,
and a branch shall grow out of his roots.
And the Spirit of the LORD shall rest upon him,
the spirit of wisdom and understanding,
the spirit of counsel and might,
the spirit of knowledge and the fear of the LORD.2

CCC 2305 Earthly peace is the image and fruit of the peace of Christ, the messianic “Prince of Peace.”3 By the blood of his Cross, “in his own person he killed the hostility,”4 he reconciled men with God and made his Church the sacrament of the unity of the human race and of its union with God. “He is our peace.”5 He has declared: “Blessed are the peacemakers.”6

1 Jn 12:41; cf. Isa 6-12.
2 Isa 11:1-2.
3 Isa 9:5.
4 Eph 2:16 J.B.; cf. Col 1:20-22.
5 Eph 2:14.
6 Mt 5:9.