In Jainism, the concept of Ayushya (lifespan) relates to the duration a soul enjoys in a particular realm (gati) based on its karmic bondage. The Devlok refers to the heavenly realms where celestial beings (devas) reside.

First Devlok specifically means the lowest of the heavenly abodes, called Saudharma Kalpa.

According to Jain scriptures, particularly the Tattvartha Sutra and commentaries such as the Gommatsar and Trilokasara, the utkrushtha ayushya (maximum lifespan) in the first Devlok (Saudharma Kalpa) is one sagaropama (सागरोपम) — an extremely long, immeasurable period.

Summary:

• First Devlok: Saudharma Kalpa
• Utkrushtha Ayushya: One sagaropama (सागरोपम)

This means a soul can enjoy heavenly pleasures in the first Devlok for a maximum of one sagaropama, as per Jain cosmological texts.