1 Kings 12:28-33

So the king consulted, and made two golden calves, and he said to them, “It is too much for you to go up to Jerusalem; behold your gods, O Israel, that brought you up from the land of Egypt.” He set one in Bethel, and the other he put in Dan. Now this thing became a sin, for the people went to worship before the one as far as Dan. And he made houses on high places, and made priests from among all the people who were not of the sons of Levi. Jeroboam instituted a feast in the eighth month on the fifteenth day of the month, like the feast which is in Judah, and he went up to the altar; thus he did in Bethel, sacrificing to the calves which he had made. And he stationed in Bethel the priests of the high places which he had made. Then he went up to the altar which he had made in Bethel on the fifteenth day in the eighth month, even in the month which he had devised in his own heart; and he instituted a feast for the sons of Israel and went up to the altar to burn incense.