On the way a Shiva devotee got an idol of Harihar. The idol was carved with half Vishnu and half Shiva. Brought the idol home.
He began to worship only Shiva who was half. Abhisheka was careful not to make offerings to Lord Vishnu whenever he performed the Veda. The scent of the sandalwood sticks to the nostrils of Vishnu so that the scent of it does not go to Vishnu.
Then Mahavishnu offered darshan to the devotee. Surprise to Lord Shiva. "I didn't do your worship, why did you come?" "Bhakta, did you worry that I would not be offered to Lord Shiva? I believe that I am inside this idol.
Temptation: The idol should be worshiped in the sense that it worships the Lord through it.