זוהר שמות — דף קצג ע”א

Aaron saw the calf and erected an altar before it to bind the impure side to a feast day. Jeroboam understood that the divine Presence dwells only in Jerusalem and made a bad decision: he made calves at Bethel and Dan. The impure side is easily drawn to any place, especially this land where it yearns to dwell. Jeroboam erected calves in two places and thereby severed the bond between Israel and their heavenly Father.