Christ on the Cross with Mary and Saint John (15th century) by Unknown - Public Domain Catholic Painting

As Passion obsession developed, so did indulgences, which reduced one's punishment for sins. In the fifteenth century, people who prayed to Christ's body could earn 300 days per limb. Thomas à Kempis, whose simple writings helped shape late-medieval piety, penned fourteen separate prayers to Christ's various body parts.

Source