The Unending Chant is a cult encounter. It first appeared in the Miskatonic Horror expansion.
The voices in your head cry out with a desparate need for more and more worshippers.
If all investigators have a "One of the Thousand" Cult Membership, you are Blessed.
Otherwise, you must choose another investigator who may choose to draw a Corruption card and gain a "One of the Thousand" Cult Membership. If he does not, you lose 2 Sanity.