At first glance, Eivor Andersen Oftestad's The Lateran Church in Rome and the Ark of the Covenant seems to offer a relatively tailored study of a particular medieval text—the Descriptio Lateranensis ecclesiae (which describes the sacred precincts of the Roman Basilica of St. John in Lateran)—and a particular holy object—the Ark of the Covenant (ostensibly housed at the Lateran church from around the turn of the twelfth century until Pope Benedict XIV removed the discredited relic in the eighteenth century). In part, her book focuses carefully on the origins, recensions, and manuscript tradition of the Descriptio Lateranensis ecclesiae, dated by Oftestad to the period just after the First Crusade rather than within the traditionally agreed upon range of between 1073 and 1118. The Descriptio Lateranensis ecclesiae, in turn, provides important evidence for the fact that the regular canons at the Lateran claimed to possess the Ark of the Covenant, among other biblical relics. According to Oftestad, this assertion legitimated the Lateran church's status as the physical successor to the destroyed Jewish temple in Jerusalem. In the appendices, Oftestad's book displays its scholarly rigor, including a list of manuscripts containing references to the Descriptio Lateranensis ecclesiae, a stemma of the text and analysis of its variant versions, and an edition of the text based on Biblioteca Apostolica Vaticana Reg. lat. 712, accompanied by a complete English translation of its contents.

Building on these finely grained foundations, however, Oftestad's work ranges far beyond the immediate orbit of the Lateran church, exposing the wider contours of surprising landscapes linked to the Descriptio Lateranensis ecclesiae and the Ark. These include, importantly, what she identifies as the concept of translatio templi—that is, the historical imagining that the Jewish temple in Jerusalem was “translated” or transferred to the Lateran in Rome. Translatio templi thereby formed an imported corollary to the better known and widespread medieval theory of translatio imperii (the translation of empire from east to west) and translatio religionis (the transferal of religious life from the eastern to western regions of the Christian world). Oftestad's careful unpacking of the Lateran church's claim to the Ark additionally leads her back to the Constitutum Constantini (commonly known as the Donation of Constantine), that famous forgery which first identified the Lateran church as the “pinnacle of Roman sacerdotal and imperial authority” (44). The Lateran's liturgical tradition reinforced this entire program, elaborated not coincidently in the period after the “Gregorian” reform, when the papacy was broadcasting its place of primacy over Christendom more aggressively than ever before.

For Oftestad, more than anything else, the capture of the earthly Jerusalem by the crusaders in 1099—including the Temple Mount—supercharged what used to be allegorical associations between Israel in the Old Testament and the church in the New Testament (evident, for example, in works of exegesis by Bruno of Segni), thereby transforming the Lateran basilica into the literal replacement for the Jewish temple. The canons at the Lateran must have also sensed the possibility of competition from the newly founded crusader church of Jerusalem. Claiming to possess the biblical Ark of the Covenant represented one way of shutting that door. Indeed, this is why Oftestad's refined dating of the Descriptio Lateranensis ecclesiae to the years after the First Crusade (specifically, after Fulcher of Chartres completed his Historia Hierosolymitana in 1106) matters, setting the production of the text firmly in a crusading context. The presence of the Descriptio Lateranensis ecclesiae in French and Belgian manuscripts, transcribed alongside crusader histories and pilgrimage guides to the Holy Land, lends additional weight to her argument about the centrality of the early crusading movement to reshaping and intensifying the Lateran's identification as the new home of the Ark and ground zero for God's covenant with his new chosen people in the Christian church.

Set into the wider scope of salvation history, the stakes in possessing the Ark were immense. As Oftestad observes: “The Ark was thus transferred both as an object from the innermost space of the Jewish temple and as an object that imitated the heavenly pattern. The transfer was a physical expression of how access to truth and the mediation between God and humankind had left the Jewish temple and was now exclusive to the Church” (132). As a holy relic, it is worth noting, the Ark posed some unique historical problems. Various traditions asserted that the Ark was lost during the Babylonian captivity or would be kept hidden until God decided otherwise; others claimed that the Romans under Titus and Vespasian had removed the Ark, restored after the Jewish return from exile in Babylon, following the sack of Jerusalem in 70. This remembrance of the Ark provided some logic for its presence in Rome. Still other traditions insisted that the Ark remained hidden somewhere in the depths of the Temple Mount.

Oftestad's book additionally explores how advocates for the presence of the Ark at the Lateran church selectively remembered its past and explained away these possible objections to the sacred object's final resting place in Rome. Or, at least, they postponed the reckoning with such possible criticisms. As Oftestad informs her readers at the start of this work and reminds them at its conclusion, eventually skepticism caught up with the Ark, deemed a fake in the eighteenth century and removed from the basilica. In a footnote to her epilogue, Oftestad indicates that she contacted the head of the Vatican museum in 2008 to ask whether anything remained of the putative Ark of the Covenant somewhere in the Vatican's collection. The curator replied that he knew nothing about this tradition, leaving the fate of the Ark a mystery.