When the Holy Spirit works on us, we preach the gospel. (Acts 1:8, Acts 2:4, 8-11)
Acts 1:8 But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth.
Acts 2:4 And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance. 8 And how hear we every man in our own tongue, wherein we were born? 9 Parthians, and Medes, and Elamites, and the dwellers in Mesopotamia, and in Judaea, and Cappadocia, in Pontus, and Asia, 10 Phrygia, and Pamphylia, in Egypt, and in the parts of Libya about Cyrene, and strangers of Rome, Jews and proselytes, 11 Cretes and Arabians, we do hear them speak in our tongues the wonderful works of God.
Acts 13:2 As they ministered to the Lord, and fasted, the Holy Ghost said, Separate me Barnabas and Saul for the work whereunto I have called them. 3 And when they had fasted and prayed, and laid their hands on them, they sent them away. 4 So they, being sent forth by the Holy Ghost, departed unto Seleucia; and from thence they sailed to Cyprus. 5 And when they were at Salamis, they preached the word of God in the synagogues of the Jews: and they had also John to their minister.