Canticle is one of many slaves found in the Cloakwood Mines during Baldur's Gate. He claims to have been a bard once, but the harsh conditions of the mine have ruined his lungs and his voice. Like most slaves in the area, he merely serves to help reinforce the setting and their predicament; in Canticle's case, his dialogue reinforces Gorion's Ward likely target - Davaeorn - while making the point that there's even more to be investigated.