Sentence:  The guru-<WSD>chela</WSD> relationship was a theme in many of Nicholas's paintings. In "Pearl of Searching", the guru is looking thoughtfully at a pearl necklace with his <WSD>chela</WSD>. This symbolizes the "pearl of great price" that gives purpose to life. 
Meaning of the word marked with <WSD> tags:  A pupil or disciple, especially in Hinduism.