The Argument
(1) Every event is caused.
(2) An infinite regress is impossible.
(3) Therefore, there was a first cause, which everyone calls God.
Comments
(1) and (2) need to be proved.
There are uncaused events in quantum mechanics.
If every event is caused by an earlier event, then an infinite regress is not only possible but actual and there can have been no first cause which, in any case, would be a past event, not an eternal person.