Albert Barnes on Luke 15:17

He came to himself. This is a very expressive phrase. It is commonly applied to one who has been deranged, and when he recovers we say he has come to himself. In this place it denotes that the folly of the young man was a kind of derangement--that he was insane. So it is of every sinner. Madness is in their hearts (Eccl 9:3); they are estranged from God, and led, by the influence of evil passions, contrary to their better judgment and the decisions of a sound mind.

Hired servants. Those in a low condition of life--those who were not born to wealth, and who had no friends to provide for them.

I perish. I, who had property and a kind father, and who might have been provided for and happy.