Philip begins with Isaiah's suffering servant
The Ethiopian official was reading Isaiah's words about the silent sufferer led to slaughter, and Philip began with that Scripture to tell him the good news about Jesus.
He was oppressed and afflicted, yet He did not open His mouth. He was led like a lamb to the slaughter, and as a sheep before her shearers is silent, so He did not open His mouth. By oppression and judgment He was taken away, and who can recount His descendants? For He was cut off from the land of the living; He was stricken for the transgression of My people.
Isaiah 53:7-8 describes the servant led like a lamb to slaughter, silent before His shearers and cut off from the land of the living; Acts 8:32-35 quotes those verses and records Philip explaining the good news about Jesus from that very Scripture.