Classical Unitarianism explicitly rejected substitutionary atonement — the idea that Christ bore divine punishment on behalf of sinners to satisfy God's wrath — as a morally offensive and theologically incoherent doctrine. Early Unitarians like William Ellery Channing argued that the concept of God requiring the death of an innocent person to forgive guilty ones was incompatible with a moral and loving God. Jesus' death was seen as an expression of faithful witness, not a sacrifice satisfying divine justice.

In contemporary UUism, the question of atonement is rarely central, as salvation in the traditional sense is not a primary religious concern for most UU members. Among those who engage with Jesus' death theologically, the most common interpretation is moral exemplarism — Jesus died because of his faithful commitment to justice and love, and his death inspires his followers to similar courage and commitment. There is no sense in which his death 'saves' anyone in the juridical or sacrificial sense of orthodox Christianity.

The UUA's universalist heritage also undermines the logic of penal substitution: if all are ultimately accepted by God (or by the universe), then there is no divine wrath requiring satisfaction by a substitutionary sacrifice. The UUA's theological orientation moves away from frameworks of guilt, punishment, and atonement toward frameworks of transformation, healing, and community.