Goldmoon’s staff hurting Raistlin

As Raistlin touched the staff, however, there was a bright flash of blue light and a crackling sound. The mage jerked his hand back, crying out in pain and shock. Caramon jumped forward, but his brother stopped him.
“No, Caramon,” Raistlin whispered hoarsely, wringing his injured hand. “The lady had nothing to do with that.”
The woman, indeed, was staring at the staff in amazement.
“What is it then?” Tanis asked in exasperation. “A staff that heals and injures at the same time?”
“It merely knows its own.” Raistlin licked his lips, his eyes glittering.
…
Reluctantly, Caramon stretched out a trembling hand. His arm twitched as his fingers came closer and closer. Closing his eyes and gritting his teeth in anticipation of pain, he touched the staff. Nothing happened.
Caramon opened his eyes wide, startled. He gripped the staff, lifted it in his huge hand, and grinned.
“See there.” Raistlin gestured like an illusionist showing off a trick to the crowd. “Only those of simple goodness, pure in heart”—his sarcasm was biting—“may touch the staff. It is truly a sacred staff of healing, blessed by some god. It is not magic. No magic objects that I have ever heard about have healing powers.”

Excerpt From Dragons of Autumn Twilight, pg 82
Margaret Weis & Tracy Hickman