The God who made the world and everything in it, being Lord of heaven and earth, does not live in temples made by man, nor is he served by human hands, as though he needed anything, since he himself gives to all mankind life and breath and everything.
Acts 17:24-25 ESV
Paul had come to Athens because the Jews had stirred up the crowd against him in Berea. While waiting for his companions to join him, he shared Jesus and the resurrection with people in the marketplace, including some philosophers who invited him to a meeting of the Areopagus (Acts 17:17-18). The Areopagus was a place for philosophical discussion and holding trials for those accused of a crime.
Paul was brought there because he was advocating what the philosophers considered to be strange teachings of foreign deities. And Luke recorded a note that said these folks would spend their time doing nothing except telling or hearing something new.
Paul began his “defense” by commenting on Athens’s vast array of idols. Including an altar to an unknown god. And he then proceeded to proclaim to them who this unknown god was.
The idol that was unknown to them was the God who made the world and everything in it. This immediately set God apart from all of the other Greek idols. While they might have power over certain aspects of the creation, there was no thought that any of them were responsible for creating the world. So, the God Paul proclaimed to them was fundamentally different from all other gods.
Following that, Paul told them that God did not dwell in human-built temples or need anything we could do for him. Instead, it is God who gives us breath and all we need for life. And Paul went on to tell them that God was the one who controlled history and nations.
In short, God did not make us for what we could do for him. There is nothing we have or can do that he needs. So why did he make us? So that we would seek him and perhaps find him (Acts 17:27). He made us so that we could experience life with him.