Adam Clarke on 1 Kings 13:9

For so it was charged me - Eat no bread, etc. - That is, Have no kind of communication with those idolaters. He was charged also not to return by the way that he came; probably lest the account of what was done should have reached the ears of any of the people through whom he had passed, and he suffer inconveniences on the account, either by persecution from the idolaters, or from curious people delaying him, in order to cause him to give an account of the transactions which took place at Beth-el. This is a reason why he should not return by the same way; but what the reason of this part of the charge was, if not the above, is not easy to see.