Oral gospel traditions, cultural information passed on from one generation to the next by word of mouth, were the first stage in the formation of the written gospels. These oral traditions included different types of stories about Jesus. For example, people told anecdotes about Jesus healing the sick and debating with his opponents. The traditions also included sayings attributed to Jesus, such as parables and teachings on various subjects which, along with other sayings, formed the oral gospel tradition.
Biblical scholars use a variety of critical methodologies known as biblical criticism. They apply source criticism to identify the written sources beneath the canonical gospels. Scholars generally understood that these written sources must have had a prehistory as oral tellings, but the very nature of oral transmission seemed to rule out the possibility of recovering them. However, in the early 20th century the German scholar Hermann Gunkel demonstrated a new critical method, form criticism, which he believed could discover traces of oral tradition in written texts. Gunkel specialized in Old Testament studies, but other scholars soon adopted and adapted his methods to the study of the New Testament.
The essence of form criticism is the identification of the Sitz im Leben, "situation in life", which gave rise to a particular written passage. When form critics discuss oral traditions about Jesus, they theorize about the particular social situation in which different accounts of Jesus were told. For New Testament scholars, this focus remains the Second Temple period. It needs be remembered that the first century Palestine of Jesus was predominantly an oral society.
A modern consensus exists that Jesus must be understood as a Jew in a Jewish environment. According to scholar Bart D. Ehrman, Jesus was so very firmly rooted in his own time and place as a first-century Palestinian Jew – with his ancient Jewish comprehension of the world, and God – that he does not translate easily into a modern idiom. Ehrman stresses that Jesus was raised in a Jewish household in the Jewish hamlet of Nazareth. He was brought up in a Jewish culture, accepted Jewish ways and eventually became a Jewish teacher, who, like other Jewish teachers of his time, debated the Law of Moses orally.Early Christians sustained these teachings of Jesus orally. Rabbis or teachers in every generation were raised and trained to deliver this oral tradition accurately. It consisted of two parts: the Jesus tradition (i.e., logia or sayings of Jesus) and inspired opinion. The distinction is one of authority: where the earthly Jesus has spoken on a subject, that word is to be regarded as an instruction or command.