The Ācārāṅga gives the guidelines for Ācāra i.e. conduct. It has, therefore, been recognised as the quintessence of all the 'Aṅgas'. The Niryuktikāra has himself raised this issue and answered that the Ācārāṅga is the soul of all the 'Aṅgas'.
It also suggests the path for emancipation, which is the most crucial part of the study.[1] We get the knowledge of the śramaṇa religion from this study and the knowledge of the Ācārāṅga is, therefore, recognized as the first 'gaṇi-sthāna' - the first consideration of an ācārya.[2] It is the basic Āgama that deals with the conduct of an ascetic. Therefore, it is studied first. Without reading the nine Brahmacharyādhyanas (of Ācārāṅga), if any monk reads the super Āgamas i.e. the successive Āgamas, he has to expiate for it.[3]
The tradition held that Dharmānuyoga (explanation of righteousness), Gaṇitānuyoga, (mathemalical explanation) and Dravyānuyoga (metaphysicl explanation) should be studied only after the Ācārāṅga has been studied.[4] A newly initiated ascetic was to be introduced first to Śastra-parijñā (comprehension and abandonment of weapons of injury) - the first chapter of the Ācārāṅga.[5] The other Aṅgas like Śūtrakṛta could be studied only after the Ācārāṅga has been understood.[6]
āyārammi ahῑe, jaṃ nāo hoi samaṇadhammo u.
tamhā āyāradharo, bhaṇṇai paḍhamaṃ gaṇiṭṭhāṇaṃ.
Niśῑtha Cūrṇi (Niśῑtha sūtra, IV"1 part), p.253: ahavā - baṃbhacerādῑ āyāraṃ avāettā dhammāṇuo isi bhāsiyādi vāeti, ahavā - sūrapaṇṇattiyāi gaṇiyāṇuogaṃ vāeti, ahavā - diṭṭhivātaṃ daviyāṇuogaṃ vāeti, ahavā - jadā caraṇāṇuogo vātitto tadā dhammāṇuyogaṃ avāettā gaṇiyāṇuyogaṃ vāeti, evaṃ ukkamo cāraṇiyāe savvo vi bhāsiyavvo.