The Majjhima Nikāya (abbreviated MN) or Collection of the Buddha's Intermediate Discourses is a collection of 152 discourses in the Pāli canon. The word "intermediate" refers to the length of each individual discourse. It contains a wide variety of teachings presented as narratives between the Buddha and a wide range of his contemporaries. The collection parallels the Madhyamāgama (MA) of the Sarvāstivāda school, which survives as a translation in the Chinese canon.
The Collection of the Buddha's Intermediate Discourses is the best known collection among the four Nikāyas containing original suttas. This popularity may be due to the fact that it mixes biographical anecdotes with very superficial doctrinal content as opposed to the Saṁyutta Nikāya.
This Intermediate Collection contains scattered and undisguised apocryphal suttas of petty intentionality, introduced very late, which detracts from its luster and credibility. However, it is interesting to note the value of the biographical references for the sake of contextualizing the Buddha in the world in which he lived.
This first sub-collection, called The First Fifty, contains fifty suttas and is divided into five chapters: the Chapter on the Root of All Things, the Chapter on the Roar of the Lion, the Chapter on Similes, the Chapter on Pairs and the Minor Chapter on Pairs.
We can highlight in this subcollection the suttas, MN 4 Fear and Awe, MN 26 The Noble Quest and MN 36 Great Discourse with Saccaka, which refer to the way in which the Buddha became enlightened, as well as autobiographical indications about his origin, who he was and the reasons why he forbade being called by his name. Also relevant are MN 10 The Four Instructions of Practice, MN 16 Mental Obstructions and MN 17 The Thickness of the Jungle.