Answer

The one Jain prayer most commonly regarded as above all others is the Namokar Mantra — also called the Navkar Mantra.

Explanation

It is the most revered mantra in Jain Dharma because it offers salutations to the five supreme beings:

• Arihants
• Siddhas
• Acharyas
• Upadhyayas
• Sadhus

Unlike many prayers, it does not ask for worldly favors. It is a prayer of pure reverence, humility, and spiritual upliftment.

Spiritual Understanding

In Jain tradition, the Navkar Mantra is considered extremely powerful because:

• it honors the highest spiritual qualities,
• it reminds us to walk the path of purity and non-attachment,
• it helps destroy pride and ego,
• and it supports inner peace and spiritual progress.

It is often regarded as the essence of Jain prayer itself.

Takeaway

If you mean the single Jain prayer held in the highest regard, it is the Navkar Mantra. It is not a prayer for asking, but a prayer for bowing in devotion to the highest ideals of Jain Dharma.