David Eddings Wiki
This page is written in the in-universe perspective of the "Garion" series' of novels.

Andorig, Baron of Vo Enderig was a knight guarding the gate at Vo Mimbre. He refused to allow entrance to Mandorallen, not believing his companions were in fact Belgarath and Polgara. To convince him, Belgarath turned a twig into a full grown apple tree, and charged Andorig with the care of the tree and to share the apples with anyone who asks.  

Years later he encounters Belgarath again, and reports he is still tending the tree. 

  "I charge thee, Sir Knight, to care for this tree. It hath grown here to renew thy faith and trust. Thy debt to it must be paid with tender and loving attention to its needs." Queen of Sorcery