Answer

Yes, a Jain layperson may use an underground metro for necessary travel.

Explanation

In Jain Dharma, the main principles to consider are:

• Ahimsa — minimizing harm to living beings
• Aparigraha — avoiding unnecessary attachment and luxury
• Samyama — using things with restraint and awareness

Using an underground metro is generally a form of public transport. If it is used for genuine needs such as work, study, seva, family duties, or necessary travel, it can be acceptable for a layperson.

However, one should remain mindful that digging underground, construction, and movement may involve harm to living beings in earth-bodied life forms. Therefore, unnecessary use, careless behavior, or using it only for luxury should be avoided.

Spiritual Understanding

Jain Dharma does not teach ordinary householders to stop all worldly activity, but to live with awareness and reduce violence as much as practically possible. The key is not only the transport itself, but the intention, necessity, and mindfulness behind its use.

Takeaway

Use the underground metro only when needed, travel mindfully, avoid wasteful trips, and keep the spirit of Ahimsa in your heart.