In Savatthi there was a young man called Wakkali who admired the Buddha's beauty. One day he thought, "So long as I am living at home I cannot see the Buddha, but if I become a monk I would see him daily." So he went to the temple and was ordained by the Buddha.
Now he had the opportunity to always admire the Buddha's appearance. He did nothing all day but follow the Buddha like a shadow. The Buddha waited for Wakkali's wisdom to ripen, saying not a word. But instead of reading, learning and meditating Wakkali just admired the Buddha. The Buddha thought, "Unless this monk gets a shock he will never come to understand."
So one day the Buddha had an invitation to spend the three months rains retreat in Rajagaha and he left Wakkali behind.
Wakkali was very disappointed and began to think, "Three months is a long time. What a miserable period I will have to spend. What is the use of living any longer? I will throw myself off Vultures' Peak."
Now the Buddha, staying in Rajagaha, saw with his mind's eye Wakkali about to jump off Vultures' Peak. "If this monk gets no comfort or consolation from me he will kill himself," he thought. The Buddha immediately sent forth a radiant image of himself and there, on the edge of the summit at Vultures' Peak, Wakkali saw the Buddha before him and felt his sorrow vanish. Wakkali's mind was filled with joy and he thought, "The person who has perfect faith in the Buddha will be full of joy and satisfaction. The person who has perfect faith in the Buddha will reach the place of peace and happiness."
(http://www.metta.lk/mirror/www.buddhanet.net/e-learning/buddhism/lifebuddha/30lbud.htm)
