In Siva temples you might have noticed a stone bull in a sitting posture in front of the God. The bull is the animal God Siva rides. So Siva temples have these carven bulls before the Linga.
At Punkanur this stone bull is so big that Nanda could not see the God inside the temple, The bull shut off the view. Nanda felt very sad because he could not see God.
At last be prayed to God Siva: "O God! I have come here all the way to see you.The bull stands between You and me.
Won't you please ask the bull to move aside a little, so that I can see You?"
God was pleased by Nanda's prayer. God asked the stone bull to move its head side ways.Lo! The bull did so, and Nanda could now see the God very well. He danced in joy and sang God's praises. Even today at Punkanur the huge stone bull can be seen. It has moved aside a little.