What does it mean to be merciful in the religious sense? Medieval theology taught that mercy flows spontaneously out of charity, like smoke from fire. It linked mercy to justice, seeing it as one dimension of justice. This insight is valuable because mercy does flow out of charity and ultimately takes its root in justice. But Fr. Rolheiser writes that it has its own specificity, which can be seen when we examine it biblically. In the Old Testament, mercy (hesed, often translated as loving-kindness) is a quality ascribed first of all to God. Later, the prophets begin challenging the people with it, telling them that God does not want sacrifice but mercy, as God practices. What is implied in this? Biblically, mercy is a word used to describe the feelings and actions that a very loving parent has towards their children. The concept of mercy connotes feelings and actions that are deeply personal, one-to-one, unique, special, tender, and warm. The tender love of a parent for a child dwarfs the demand for strict justice even while never violating it. The church classically taught this through various lists, which tried to summarize what is implied in imitating God’s mercy. The corporal works of mercy: feeding the hungry, giving drink to the thirsty, clothing the naked, sheltering the homeless, visiting the sick, ransoming the captive, bury the dead are one such list. In essence, these lists challenge us to be more holy and God-like through practicing a justice that is more personal, one-to-one, warm, and gracious beyond strict need. The prophets of the Old Testament made this list the acid test for faith. If you did these things, you had faith – and vice versa. Jesus goes even further. For him, as is evident in Matthew’s Gospel, the corporal works of mercy are the criteria for salvation and the measure of how we are treating him – “Whatsoever you do unto the hungry, thirsty, naked, homeless, sick, and captive, you do unto me.” Long buried in the thicket, the list of the corporal works of mercy awaits such exploration.