Q source in the context of Three-source hypothesis

The Gospel of Luke is the third of the New Testament's four canonical Gospels. It tells of the origins, birth, ministry, death, resurrection, and ascension of Jesus. Together with the Acts of the Apostles, it makes up a two-volume work which scholars call Luke–Acts, accounting for 27.5% of the New Testament.

The text is anonymous, not naming its author. Perhaps most scholars think that he was a companion of Paul, but others cite differences between him and the Pauline epistles. In the popular Two-source hypothesis, Luke used the Gospel of Mark and a hypothetical collection called Q, with unique material often called L, though alternative hypotheses that posit the direct use of Matthew by Luke or vice versa without Q are increasing in popularity within scholarship. Luke follows Mark closely compared to other ancient historians’ usage of sources, though the parallels and variations of the Synoptic gospels are typical of ancient historical biographies. Luke tends to follow his sources closely when checked. The most common dating for its composition is around AD 80–90. The earliest witnesses for the Gospel of Luke are the Alexandrian and the revised western text-type.

The gospels of Matthew, Mark, and Luke are referred to as the synoptic Gospels because they include many of the same stories, often in a similar sequence and in similar or sometimes identical wording. They stand in contrast to John, whose content is largely distinct. The term synoptic (Latin: synopticus; Greek: συνοπτικός, romanized: synoptikós) comes via Latin from the Greek σύνοψις, synopsis, i.e. "(a) seeing all together, synopsis". The modern sense of the word in English is of "giving an account of the events from the same point of view or under the same general aspect". It is in this sense that it is applied to the synoptic gospels.

This strong parallelism among the three gospels in content, arrangement, and specific language is widely attributed to literary interdependence, though the role of orality and memorization of sources has also been explored by scholars. The question of the precise nature of their literary relationship—the synoptic problem—has been a topic of debate for centuries and has been described as "the most fascinating literary enigma of all time". While no conclusive solution has been found yet, the longstanding majority view favors Marcan priority, in which both Matthew and Luke have made direct use of the Gospel of Mark as a source, and further holds that Matthew and Luke also drew from an additional hypothetical document, called Q, though alternative hypotheses that posit direct use of Matthew by Luke or vice versa without Q are increasing in popularity within scholarship.

The two-source hypothesis (or 2SH) is an explanation for the synoptic problem, the pattern of similarities and differences between the three Gospels of Matthew, Mark, and Luke. It posits that the Gospel of Matthew and the Gospel of Luke were based on the Gospel of Mark and a hypothetical sayings collection from the Christian oral tradition called Q.

The two-source hypothesis emerged in the 19th century. B. H. Streeter definitively stated the case in 1924, adding that two other sources, referred to as M and L, lie behind the material in Matthew and Luke respectively. The strengths of the hypothesis are its explanatory power regarding the shared and non-shared material in the three gospels; its weaknesses lie in the exceptions to those patterns, and in the hypothetical nature of its proposed collection of Jesus-sayings. Later scholars have advanced numerous elaborations and variations on the basic hypothesis, and even completely alternative hypotheses that are increasing in popularity. Nevertheless, "the 2SH commands the support of most biblical critics from all continents and denominations."

M source, which is sometimes referred to as M document, or simply M, comes from the M in "Matthean material". It is a hypothetical textual source for the Gospel of Matthew. M Source is defined as that "special material" of the Gospel of Matthew that is neither Q source nor Mark.

The Q+/Papias hypothesis (Q+/PapH), advanced by Dennis R. MacDonald, offers an alternative solution to the synoptic problem. MacDonald prefers to call this expanded version of Q Logoi of Jesus, which is supposed to have been its original title.

The Q+/PapH has similarities to previous solutions to the synoptic problem. Like the two-source hypothesis, the Q+/PapH affirms that both Matthew and Luke have used a Q document. Like the Farrer hypothesis, it affirms that Matthew used Mark and that Luke used both Mark and Matthew. Like the modified two-document hypothesis, it affirms that Mark also used the Q document.

The Gospel of Thomas (also known as the Coptic Gospel of Thomas) is a non-canonical sayings gospel. It was discovered near Nag Hammadi, Egypt, in 1945 among a group of books known as the Nag Hammadi library. Scholars speculate the works were buried in response to a letter from Bishop Athanasius declaring a strict canon of Christian scripture. Most scholars place the composition during the second century, while some have proposed dates as late as 250 AD and others have traced its signs of origins back to 60 AD. Some scholars have seen it as evidence of the existence of a "Q source" that might have been similar in its form as a collection of sayings of Jesus, without any accounts of his deeds or his life and death, referred to as a sayings gospel, though most conclude that Thomas depends on or harmonizes the Synoptics.

The Coptic-language text, the second of seven contained in what scholars have designated as Nag Hammadi Codex II, comprises 114 sayings attributed to Jesus. Almost two-thirds of these sayings resemble those found in the canonical gospels and its editio princeps counts more than 80% of parallels. Experts speculate that the gospel's other sayings were added from Gnostic tradition. Its place of origin may have been Syria, where Thomasine traditions were strong. Other scholars have suggested an Alexandrian origin.