"Then Philip opened his mouth, and beginning at this Scripture, preached Jesus to him."
Anywhere we turn in our Bibles we find, ultimately, the very same message: it is that the Son of God would be/is incarnated, crucified, resurrected, and glorified. Some texts, like the Isaiah passage that Philip expounded to the Ethiopian, are more specific than others--but every jot and tittle of the OT, and every Greek letter of the NT speaks of Jesus.
Let this inform us as we study the Scriptures, and when we share its truth with others. If we do not "preach Jesus to [them]," we are doing them no service at all.
[Puritan quote of the day: "The love of Christ for the elect is so great that God the Father looks upon it proper and suitable to account Christ and the elect as one, and accordingly to account what Christ does and suffers as if they did it and suffered it." --Jonathan Edwards, in his sermon entitled, "The Wisdom of God"]