"Mentoring is a relatively recent term, especially in Christian circles, but what it describes has been the focus of Christian community since the early church. It is a dynamic relationship of trust in which one person enables another to maximise the grace of God in their life and service. It has a sound biblical and theological basis with Jesus as the ultimate model, retaining all that is consistent with his life and teaching."
from "Mentoring to Develop Disciples and Leaders" by John Mallison, 2006.
World champion tennis coach John Newcombe was once asked about the most important thing he does for young tennis players he mentors. He said that it is giving encouragement. While they needed skill and motivation, he said, without encouragement they would give up.
Its worth looking at the historical background to the notion.
The word actually dates back to ancient Greece, where a man named Mentor acted as a advisor and life coach to the young nobleman Telemachus.