Answer

In the fourth ara (Chaturth Ara), it is not one specific person’s heart that fails. In Jain cosmology, people in general become weaker in body, mind, lifespan, and moral strength during this era.

Explanation

According to Jain tradition, the fourth ara is a time of decline. During this period:

• physical strength decreases
• lifespan becomes shorter
• virtues and discipline reduce
• anger, greed, and delusion increase

So if you mean “whose heart fails,” the correct idea is that the hearts of people in that age become कमजोर / कमजोर-minded in the sense of declining courage, purity, and stability.

Spiritual Understanding

The teaching of the fourth ara reminds us that worldly conditions are not permanent. Jain Dharma encourages us to stay alert, disciplined, and detached even in times of decline.

Takeaway

In the fourth ara, all beings experience decline, not just one person. It is a collective weakening of human strength and values.