Acts 8:36-40 (ESV)
And as they were going along the road they came to some water, and the eunuch said, “See, here is water! What prevents me from being baptized?” And he commanded the chariot to stop, and they both went down into the water, Philip and the eunuch, and he baptized him. And when they came up out of the water, the Spirit of the Lord carried Philip away, and the eunuch saw him no more, and went on his way rejoicing. But Philip found himself at Azotus, and as he passed through he preached the gospel to all the towns until he came to Caesarea.
The preaching of the Gospel brings about salvation:
Romans 16:25-27 (ESV)
Now to him who is able to strengthen you according to my gospel and the preaching of Jesus Christ, according to the revelation of the mystery that was kept secret for long ages but has now been disclosed and through the prophetic writings has been made known to all nations, according to the command of the eternal God, to bring about the obedience of faith— to the only wise God be glory forevermore through Jesus Christ! Amen.
Philip first began his ministry waiting on tables:
Acts 6:3-6 (ESV)
Therefore, brothers, pick out from among you seven men of good repute, full of the Spirit and of wisdom, whom we will appoint to this duty. But we will devote ourselves to prayer and to the ministry of the word.” And what they said pleased the whole gathering, and they chose Stephen, a man full of faith and of the Holy Spirit, and Philip, and Prochorus, and Nicanor, and Timon, and Parmenas, and Nicolaus, a proselyte of Antioch. These they set before the apostles, and they prayed and laid their hands on them.
He then became a proclaimer of truth. He started in the kitchen and ended up in the pulpit. That is what God does. With the power of God’s word lives are changed by those whose lives have also been changed.
Luke 16:10 (ESV)
“One who is faithful in a very little is also faithful in much, and one who is dishonest in a very little is also dishonest in much.