1 Kings 13:1,4 King James Version (KJV)
And, behold, there came a man of God out of Judah by the word of the Lord unto Bethel: and Jeroboam stood by the altar to burn incense.
And he cried against the altar in the word of the Lord, and said, O altar, altar, thus saith the Lord; Behold, a child shall be born unto the house of David, Josiah by name; and upon thee shall he offer the priests of the high places that burn incense upon thee, and men's bones shall be burnt upon thee.
And he gave a sign the same day, saying, This is the sign which the Lord hath spoken; Behold, the altar shall be rent, and the ashes that are upon it shall be poured out.
And it came to pass, when king Jeroboam heard the saying of the man of God, which had cried against the altar in Bethel, that he put forth his hand from the altar, saying, Lay hold on him. And his hand, which he put forth against him, dried up, so that he could not pull it in again to him.

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.