Within the Theravāda tradition, the discourses preserved in the Sutta Piṭaka are accompanied by a rich body of classical exegesis. The primary layer of this literature consists of the commentaries, or Aṭṭhakathā, which are largely attributed to the great systematizer Buddhaghosa and to other early scholars such as Dhammapāla. These works do not merely gloss difficult words; they unfold doctrinal nuances, narrative background, and interpretive traditions that were transmitted alongside the canonical texts. In this way, the Sutta Piṭaka is not left as a bare collection of discourses but is framed by an inherited understanding that has shaped how practitioners and scholars have approached it for centuries.

These principal commentaries are organized around the Nikāyas and certain books of the Khuddaka collection. Among the most prominent are the *Sumangalavilāsinī* on the Dīgha Nikāya, the *Papañcasūdanī* on the Majjhima Nikāya, the *Sāratthappakāsinī* on the Saṃyutta Nikāya, and the *Manorathapūraṇī* on the Aṅguttara Nikāya. For texts in the Khuddaka Nikāya, works such as the *Paramatthajotikā* and other related commentaries provide guidance on shorter and often more enigmatic compositions. Together, these Aṭṭhakathā form a kind of traditional lens through which the Suttas are read, preserving older Sinhalese interpretive strands in a polished Pāli form.

A further layer of reflection is found in the sub-commentaries, or Ṭīkā, which take the earlier commentaries themselves as their subject. These texts refine, expand, and sometimes clarify the positions of the Aṭṭhakathā, addressing ambiguities and exploring alternative readings. Sub-commentaries exist for the major Nikāya commentaries—such as Ṭīkā on the *Sumangalavilāsinī*, the *Papañcasūdanī*, and the other Nikāya commentaries—and are associated with later Theravāda scholars, including figures like Dhammapāla and Sāriputta Thera. In traditional monastic education, this layered corpus of commentary and sub-commentary functions as an indispensable guide, allowing the Sutta Piṭaka to be approached not as an isolated scriptural collection, but as part of a living, interpretive continuum.