Who Was the First Person to Attain Moksha in Jainism?

Short answer: in the Svetambara account it is Marudevi Mata, the mother of Rishabhdev — and the Digambara tradition does not accept that account. The question also has a second, more precise answer, which is that in absolute terms there is no first liberated soul at all.

Why "first" needs a frame

Jain cosmology holds that time is beginningless and cyclical. It turns through utsarpini (ascending) and avasarpini (descending) half-cycles without end, and souls have been reaching moksha throughout. So there is no first siddha in an absolute sense — the Siddhashila has been filling for beginningless time.

The question is therefore always asked within the present avasarpini: who is the first soul of this half-cycle in Bharat kshetra to reach liberation? On that, the traditions diverge.

The Svetambara account: Marudevi Mata

Marudevi, mother of Rishabhdev (Adinath, the first Tirthankara), had grieved for her son through the thousand years of his ascetic wandering, convinced he was suffering. When word came that he had attained kevala jnana, Bharat brought her to see him.

The account is deliberately pointed. Riding an elephant toward the samavasarana — surrounded by the assembly, the divine sound, the sheer evidence of what her son had become — her grief fell away, and with it her attachment. She attained kevala jnana and then moksha on the spot, before she ever reached him.

Two things make the episode carry weight in Svetambara teaching:

• She was never initiated. Marudevi took no diksha, kept no long tapasya, and belonged to no order. Liberation came from the collapse of attachment itself.
• She reached it before the Tirthankara did. Rishabhdev attained nirvana later, at Ashtapada. His mother preceded him.

The Digambara position

Digambara doctrine holds stri-moksha to be impossible — that liberation cannot be attained from a female body, and that a soul must first be reborn male. That position rules out the Marudevi account as Svetambaras tell it, and it is the same disagreement that produces the tradition's other well-known split: whether Malli, the nineteenth Tirthankara, was a woman (Svetambara) or a man, Mallinath (Digambara).

In the Digambara telling of this half-cycle, the early liberations are those of Rishabhdev, who attained nirvana at Mount Kailash, and of his son Bahubali.

The related question people usually mean

Many who search this are really asking about Bahubali, and the sequence there is not disputed: Bahubali attained kevala jnana after a year of motionless kayotsarga, but after his father Rishabhdev had attained both omniscience and liberation. Bahubali did not precede Adinath.

So the ordering the tradition gives for this avasarpini is: Marudevi (in the Svetambara account), then Rishabhdev, then Bahubali.

Related: Can women attain moksha · Can human attain moksha