Deuteronomy 17
15 Ref Then see that you take as your king the man named by the Lord your God: let your king be one of your countrymen, not a man of another nation who is not one of yourselves.
16 Ref And he is not to get together a great army of horses for himself, or make the people go back to Egypt to get horses for him: because the Lord has said, You will never again go back that way.