Would think a heap of someone?

Hi
Please guide me to know the meaning of this sentence"Eilijah would think aheap of you" in the passage bellow:

“t was to the city that the prophets came and he was here in the midst of it. He was here enjoying what should have repelled him. His lids narrowed with caution and he looked at his uncle who was rolling on ahead of him, no more concerned with it all than a bear in the woods. "What kind of prophet are you?" the boy hissed.
His uncle paid him no attention, did not stop. "Call yourself a prophet!" he continued in a high rasping carrying voice.
? of ?183His uncle stopped and turned. "I'm here on bidnis, " he said mildly. "You always said you were a prophet, " Tarwater said. "Now I see what kind of prophet you are. Elijah would think a heap of you. "
His uncle thrust his head forward and his eyes began to bulge. "I'm here on bidnis, " he said. "If you been called by...