Albert Schweitzer in the context of "Union with Christ"

The quest for the historical Jesus consists of academic efforts to determine what words and actions, if any, may be attributed to Jesus, and to use the findings to provide portraits of the historical Jesus. Conventionally, since the 18th century three scholarly quests for the historical Jesus are distinguished, each with distinct characteristics and based on different research criteria, which were often developed during each specific phase. These quests are distinguished from earlier approaches because they rely on the historical method to study biblical narratives. While textual analysis of biblical sources had taken place for centuries, these quests introduced new methods and specific techniques to establish the historical validity of their conclusions.

The enthusiasm shown during the first quest diminished after Albert Schweitzer's critique of 1906 in which he pointed out various shortcomings in the approaches used at the time. The second quest began in 1953 and introduced a number of new techniques but reached a plateau in the 1970s. In the 1980s, a number of scholars gradually began to introduce new research ideas, initiating a third quest characterized by the latest research approaches. Since the late 2000s, concerns have been growing about the usefulness of the criteria of authenticity and proclamations of a more expansive and genuinely interdisciplinary Next Quest.

Inaugurated eschatology is the belief in Christian theology that the end times were inaugurated in the life, death and resurrection of Jesus, and thus there are both "already" and "not yet" aspects to the Kingdom of God. George Eldon Ladd suggests that the Kingdom of God is "not only an eschatological gift belonging to the Age to Come; it is also a gift to be received in the old aeon."

This approach was first developed by Geerhardus Vos, especially in his 1930 work, The Pauline Eschatology. Later, Oscar Cullmann sought to combine the "thorough-going eschatology" of Albert Schweitzer with the "realized eschatology" of C. H. Dodd. Cullmann suggested the analogy of D Day and V Day to illustrate the relationship between Jesus's death and resurrection on the one hand, and his Second Coming on the other.

Consistent eschatology (thorough-going eschatology) is a theory in theological and biblical studies that interprets Jesus "in exclusively eschatological terms". The view was initiated by Johannes Weiss, and "picked up, developed, and popularized" by Albert Schweitzer.It is an exclusive futuristic eschatology, the consistent interpretation of Jesus' eschatology as an expectation of an imminent end, and the thorough-going eschatology, the first position by Schweitzer. He used a thorough eschatology to provide a solution to the historical problems associated with Jesus' life. According to this view, asserted by Johannes Weiss (J. Weiß), the proclamation of Jesus, his actions and ministry are dominated by the eschatological expectation of the impending return. (For example, "the kingdom of God is at hand”. Mk. 1:15)

It has been described by one critic (George Eldon Ladd) as picturing: