Spirit Directed Ministry
Philip's evangelistic ministry in Samaria was effective. People were hungry for God's Word and many believed in Jesus (Acts 8:12). We do not know the timing, but it seems that in the middle of Philip's mission, the Lord told him to move on, taking a southerly route which met the road from Jerusalem to Gaza. There were no further instructions. Philip obeyed, not knowing what situation he might find.
Somewhere along that east-west road leading to the coast, and the coastal north-south road to Egypt, Philip encountered chariots. The main vehicle carried the chief treasury minister for the Kingdom of Kush (Ethiopia) which was immediately south of Egypt (where Sudan is today). The modern day Ethiopia is still further south. The Kingdom was ruled by a woman, Queen Kandake (Candace). Rich monarchs in those days liked to appoint eunuchs because they were infertile, could have no family and were unlikely to be a threat to the throne.
This eunuch was God-fearing. He had been to worship in Jerusalem, but because he was a eunuch he was forbidden to enter the temple worship area (Deuteronomy 23:1); presumably he had to stay in the Court of the Gentiles. Although he had a highly paid job and was trusted by the Queen, he could not worship with God's people. Yet he was spiritually hungry and would have heard about Jesus. It was a frustrating situation and yet he did what he could: he read God's Word. The Spirit told Philip to go to the chariot and stay close to it. God had work for Philip to do (Acts 8:30-39).
God knows what He is going to do, and who He wants to help Him. He looks for believers who are prepared to follow His instructions, step by step, without knowing what the assignment will be. Sometimes He moves us from being spiritually fruitful with many people, to a desert or just a single person. The Holy Spirit has His way of telling us to move or stay, to continue as we are or to change course. Even when He does change our circumstances He may not immediately reveal what He wants us to do. But He will get us to the right place at the right time and often let us wait until He commands the moment of ministry. So be willing to let Him direct you; and wait for His timing.