In Jain dharma, Tirthankar ka sharirik upasthit rehna moksha ke liye “zaroori shart” nahi hai.

Let’s separate the ideas clearly:

1. Who is a Tirthankar and who is a Kevali?

• Tirthankar

- A keval-jñani (omniscient) who: - Re‑discovers and organizes the true dharma in a time when it has disappeared. - Establishes the tirth – the fourfold sangh (sādhu, sādhvī, śrāvaka, śrāvikā). - So “Tirthankar” is a special role among keval-jñanis.

• Kevalī (Keval-jñānī)

- Any soul who has destroyed all ghātiyā karmas and attained keval‑jñān (perfect knowledge). - Every Tirthankar is a Kevalī, but not every Kevalī is a Tirthankar.

2. Can a non‑Tirthankar Kevalī guide others to moksha?

Yes. In Jain siddhānt, any Kevalī is sarvajña (all‑knowing) and vitaraag (completely passionless). So:

• He fully knows the path of moksha.
• His teachings are free from attachment, aversion, and error.
• If beings follow his teachings with samyak‑darshan, samyak‑jñān, samyak‑chāritra, they can attain moksha.

The presence of a Tirthankar is not a compulsory condition for another soul’s liberation. The compulsory condition is:

• existence of true Jain dharma (right doctrine and conduct), and
• a living source of that pure teaching (which can be a Tirthankar, a Kevalī, or ācāryas in his tradition, while the true dharma still survives).

3. Traditional example

• After Bhagwan Mahavir attained moksha, there was no Tirthankar alive, but:

- Jambusvami became a Kevalī. - Many souls progressed and attained high spiritual states, and moksha also occurred in that period.

• This clearly shows:

Moksha continued even after the last Tirthankar’s nirvana, as long as Kevalīs and the true dharma were present.

Both Digambar and Shvetambar traditions agree on the main point:

• Jambusvami is the last Kevalī of this avasarpinī.
• After the era when Kevalīs and true dharma disappear, no new soul attains moksha in this part of the time‑cycle.

This proves:

• Tirthankar is the original establisher and organizer of the path.
• A Kevalī (even if not a Tirthankar) can guide others to moksha, provided:

- he teaches the same pure path, and - beings follow it with right faith, knowledge, and conduct.

4. Direct answer to your hypothetical

> If there is a person who attained keval gyan under guidance of a Tirthankar, and later only that Kevalī remains (no Tirthankar present), can he guide others to attain moksha?

Yes. Such a Kevalī can guide others to moksha. Tirthankar’s physical presence is not “must” at that later time. What is “must” is:

• the unchanged path originally revealed by Tirthankars, and
• a perfectly enlightened, passionless teacher (Kevalī) or authentic lineage preserving that path.

So, in Jain dharma:

• Moksha depends on tattva (right principles), not on proximity to a particular body.
• Tirthankars are the supreme founders of the ford,

but any Kevalī teaching their same dharma can be a true guide to liberation.