This paper investigates the reasons for the unexpected importance acquired by the Qubbat al-Ṣaḫrah in Crusader Jerusalem and its relationship to the Basilica of the Holy Sepulcher. It will be argued that Crusader pilgrims regarded the Qubbat al-Ṣaḫrah as the eschatological Temple or Solomon's Temple because of their knowledge of the Scriptures and local Jewish and Islamic traditions regarding the Temple Mount/ḥaram al-šarīf. Consequently, the Crusader rulers' adaptation of the Qubbat al-Ṣaḫrah as the church of the Templum Domini and its identification as Herod's Temple will be explained as a reaction to these interpretations, which risked re-establishing the pre-Christian centrality of the Temple, thus jeopardizing the supremacy of the Basilica of the Holy Sepulcher.