Rather, “in the word of the Lord.” The meaning seems to be, not merely that the prophet was bid to come, but that he came in the strength and power of God’s word, a divinely inspired messenger. (Compare 1 Kings 13:2, 1 Kings 13:5,1 Kings 13:32.)
By the altar - “On the altar;” i, e. on the ledge, or platform, halfway up the altar, whereupon the officiating priest always stood to sacrifice. Compare 1 Kings 12:32 note.