The installation of a linga involved a Hindu ritual for consecration (making it sacred and powerful).
Brahmin priests would be called to serve as channels for divine energy from the god to enter the linga during the ceremony.
Their recitation of Sanskrit mantras and their pure bodily state made it possible for the divine force to come through them into the linga.
We can a see a parallel between this and animistic rituals centered on worshiping deities in rocks and other natural objects.