Answer

In Jain Dharma, there is no fixed hour of the day that is universally forbidden for chanting a mantra. Mantras like the Navkar Mantra may be chanted at any time with a pure mind and reverence.

Explanation

What matters most is bhav — the inner feeling, concentration, and purity.

Traditionally, it is best to avoid chanting when:

• the body is in an impure state
• you are eating or drinking
• you are sleepy, angry, or careless
• you are in a place or situation that is not respectful for prayer

Many people prefer chanting in the:

• early morning
• quiet hours
• before beginning daily work
• before meditation or samayik

Spiritual Understanding

In Jainism, mantra chanting is not only about the clock. It is about:

• right intention
• mental purity
• devotion
• self-discipline

So the best time is the time when your mind is calm, respectful, and focused.

Takeaway

No special hour is strictly banned, but chant when your mind and body are pure and शांत. If you mean a specific mantra or ritual, I can explain the traditional timing for that too.