Immaculate Conception
Mary was preserved from original sin.
This doctrine is actively contested between major traditions. Faithful Christians disagree.
What the traditions say
Roman Catholic
affirms_strongly
Catholic
Dogma since 1854 (Ineffabilis Deus). Mary was preserved from original sin from the moment of her conception by a singular grace of God.
Lutheran
rejects
Lutheran
Luther initially accepted it but later Lutheranism rejected it as unscriptural. Mary is honored but not exempted from the human condition.
Eastern Orthodox
rejects
Orthodox
Orthodoxy honors Mary's sinlessness but rejects the specific mechanism of the Immaculate Conception. It presupposes Augustine's understanding of original sin, which Orthodoxy does not share.
Reformed
rejects
Reformed
No scriptural basis. Mary was a sinner saved by grace like all believers. Rom 3:23 — "all have sinned." The doctrine is seen as a post-biblical development.