In Christian art, "pieta" - the Italian for "pity" or "mercy" - is a depiction of the dead Christ following the descent from the cross, accompanied either by a sorrowful Virgin/Madonna (sometimes with Saint John), or angels. The image may be a sculpture - most often a marble sculpture or a wood carving - or a painting. The most famous Pieta is the sculpture by Michelangelo, which can be seen in St Peter's Basilica, Rome.
The Pieta is not unlike the Lamentation of Christ, taken from the Passion, except it is more reflective, and its most common form is one consisting only of the dead Jesus lying on the lap of the Virgin Mary. Indeed, if Christ and the Virgin are surrounded by too many figures, the work can lose its meditative character, and become a Lamentation. Another important difference between a Pieta and a Lamentation, is that while the latter represents a particular biblical scene from Christ's Passion, the former is a timeless image.