Tittha Jataka While at Jetavana the Buddha told this story about a monk, an ex-goldsmith, who was a co-resident of Sariputta, one of the Buddha's chief disciples. The Tathagata has the knowledge and can read the heart and thoughts of men; but because of lack of this power Sariputta had little knowledge of the heart and thoughts of his co-resident. Thus he gave him impurity as the subject for his meditation. This was no good to him. According to tradition he had been born as a goldsmith for five hundred successive births; as a result of seeing pure gold for so long the subject of impurity was useless to him. He spent for months hard at work on what Sariputta had given him without being able to get the slightest idea of it. Sariputta finding himself unable to cause his co-resident to win Arahatship thought to himself: "This is one whom only the Buddha can convert." So early one morning he went with him to the Buddha.
Tittha Jataka 1/8