When you invoke and visualize buddhas, they are actually there. Buddhas are omniscient and omnipresent. When the full moon is out, it appears effortlessly reflected in any body of water. Your faith is like the water; when you have the water of faith, the moon of the buddhas’ presence will arise.
Gyumed Khensur Lobsang Jampa. The Easy Path: illuminating the First Panchen Lama’s secret instructions. Wisdom Publications: 2013.