Answer

In most common usage, Deravasi and Mandirmargi mean the same thing.

They refer to Jain communities, especially within the Śvetāmbara tradition, who worship in temples and accept mūrti-pūjā — devotional worship of Tirthankar images.

Explanation

The terms are used slightly differently by region and context:

• Deravasi comes from the word derasar, meaning a Jain temple. So Deravasi means those who go to or worship in derasars.
• Mandirmargi means those who follow the temple path — mandir means temple and margi means follower of a path.

So both generally refer to temple-going Śvetāmbara Jains who revere Tirthankar idols in derasars or mandirs.

They are often contrasted with Sthānakavāsī and Terāpanthī Śvetāmbara Jains, who do not practice image worship and focus on prayer, meditation, sāmāyik, pratikraman, and discourses in places like upāśrayas or sthānaks rather than idol worship in temples.

Spiritual Understanding

For Deravasi or Mandirmargi Jains, temple worship is not considered worship of a creator God. In Jain Dharma, Tirthankars are perfected souls who have conquered attachment, hatred, and karma.

The image of a Tirthankar is used as a sacred focus to develop:

• devotion,
• purity of thought,
• humility,
• detachment,
• and inspiration to follow the path of liberation.

Takeaway

Deravasi and Mandirmargi are essentially two names for the same temple-worshipping Śvetāmbara Jain tradition. The difference is mainly in wording, not in religious practice.