Isa 61:1-3, Acts 10:36-38, Rom 10:14-15, Eph 2:12-17
In the Old Testament, Isaiah proclaimed that God would set the Israelites free from the Babylonian captivity. It also means that in the future Christ will set us free from sin and the hands of Satan. (Isa 52:7-10)
Isa 52:7 How beautiful upon the mountains are the feet of him that bringeth good tidings, that publisheth peace; that bringeth good tidings of good, that publisheth salvation; that saith unto Zion, Thy God reigneth! 8 Thy watchmen shall lift up the voice; with the voice together shall they sing: for they shall see eye to eye, when the Lord shall bring again Zion. 9 Break forth into joy, sing together, ye waste places of Jerusalem: for the Lord hath comforted his people, he hath redeemed Jerusalem. 10 The Lord hath made bare his holy arm in the eyes of all the nations; and all the ends of the earth shall see the salvation of our God.
In the Old Testament, it was foretold that the Spirit of God would come upon Christ and that Christ would preach the gospel. (Isa 61:1-3)
Isa 61:1 The Spirit of the Lord God is upon me; because the Lord hath anointed me to preach good tidings unto the meek; he hath sent me to bind up the brokenhearted, to proclaim liberty to the captives, and the opening of the prison to them that are bound; 2 To proclaim the acceptable year of the Lord, and the day of vengeance of our God; to comfort all that mourn; 3 To appoint unto them that mourn in Zion, to give unto them beauty for ashes, the oil of joy for mourning, the garment of praise for the spirit of heaviness; that they might be called trees of righteousness, the planting of the Lord, that he might be glorified.
As prophesied in the Old Testament, Christ Jesus came to bring us the gospel of peace. (Acts 10:36-38, Romans 10:14-15)
Acts 10:36 The word which God sent unto the children of Israel, preaching peace by Jesus Christ: (he is Lord of all:) 37 That word, I say, ye know, which was published throughout all Judaea, and began from Galilee, after the baptism which John preached; 38 How God anointed Jesus of Nazareth with the Holy Ghost and with power: who went about doing good, and healing all that were oppressed of the devil; for God was with him.
Romans 10:14 How then shall they call on him in whom they have not believed? and how shall they believe in him of whom they have not heard? and how shall they hear without a preacher? 15 And how shall they preach, except they be sent? as it is written, How beautiful are the feet of them that preach the gospel of peace, and bring glad tidings of good things!
The gospel of Christ's peace was also preached to the Gentiles. (Eph 2:12-17)
Eph 2:12 That at that time ye were without Christ, being aliens from the commonwealth of Israel, and strangers from the covenants of promise, having no hope, and without God in the world: 13 But now in Christ Jesus ye who sometimes were far off are made nigh by the blood of Christ. 14 For he is our peace, who hath made both one, and hath broken down the middle wall of partition between us; 15 Having abolished in his flesh the enmity, even the law of commandments contained in ordinances; for to make in himself of twain one new man, so making peace; 16 And that he might reconcile both unto God in one body by the cross, having slain the enmity thereby: 17 And came and preached peace to you which were afar off, and to them that were nigh.