Jer 1:17-19, Acts 18:9, Acts 26:17-18
In the Old Testament, God was with Jeremiah and had Jeremiah preach the gospel of salvation. (Jeremiah 1:7-8, Jer 1:17-19)
Jeremiah 1:7 But the Lord said unto me, Say not, I am a child: for thou shalt go to all that I shall send thee, and whatsoever I command thee thou shalt speak. 8 Be not afraid of their faces: for I am with thee to deliver thee, saith the Lord.
Jer 1:17 Thou therefore gird up thy loins, and arise, and speak unto them all that I command thee: be not dismayed at their faces, lest I confound thee before them. 18 For, behold, I have made thee this day a defenced city, and an iron pillar, and brasen walls against the whole land, against the kings of Judah, against the princes thereof, against the priests thereof, and against the people of the land. 19 And they shall fight against thee; but they shall not prevail against thee; for I am with thee, saith the Lord, to deliver thee.
God sent Paul to Israel and the Gentiles to preach the gospel of God's salvation. (Acts 18:9, Acts 26:17-18)
Acts 18:9 Then spake the Lord to Paul in the night by a vision, Be not afraid, but speak, and hold not thy peace:
Acts 26:17 Delivering thee from the people, and from the Gentiles, unto whom now I send thee, 18 To open their eyes, and to turn them from darkness to light, and from the power of Satan unto God, that they may receive forgiveness of sins, and inheritance among them which are sanctified by faith that is in me.