Analysis of information sources in references of the Wikipedia article "Assumption of Mary" in English language version.
Many early Lutherans retained the Feast of the Assumption in the liturgical calendar, while recognizing it as a speculation rather than a dogma. However, Pope Pius XII dogmatized this belief in 1950 in his decree Munificentissimus Dei (sic), thus imposing it as doctrine upon Roman Catholics. ... Today's feast is described in Lutheran Service Book as 'St. Mary, Mother of our Lord'.
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: CS1 maint: publisher location (link)There is no direct testimony in Scripture concerning the end of Mary's life. However, certain passages give instances of those who follow God's purposes faithfully being drawn into God's presence. Moreover, these passages offer hints or partial analogies that may throw light on the mystery of Mary's entry into glory.