If a muslim comes in our(bohra`s) masjid for prayer what we should do?
In the name of Allah, We praise Him, seek His help and ask for His forgiveness. Whoever Allah guides none can misguide, and whoever He allows to fall astray, none can guide them aright. We bear witness that there is no one (no idol, no person, no grave, no prophet, no imam, no dai, nobody!) worthy of worship but Allah Alone, and we bear witness that Muhammad(saws) is His slave-servant and the seal of His Messengers.
The mosques are the declared houses of Allah, and no muslim has a right to stop another muslim from worshipping Allah in any house of Allah. Thus if any muslim comes to any mosque, nor matter what are the differences are, no one has a right to stop the person from worshipping Allah in the mosques.
It is a grave sin for anyone to stop a muslim from entering any mosque, and thus stopping him from worshipping Allah Subhanah.
Allah says in the Holy Quran Chapter 72 Surah Jinn verses 18-19: And that the mosques are for Allah. Therefore, do not call upon anyone else in them along with Allah. And that when the servant of Allah stood up to invoke Him, the people got ready to assault him.
The truth is brother, that these sects of Shias, Sunnis, Bohras, etc. are all man made and have absolutely no basis in Islam. Islam is One Ummah, and anyone who propagates breaking this Ummah into sects and sub-sects is going against the clear commands of Allah Subhanah, and will be severely accountable in the Court of Allah on the Day of Judgement.
Allah says in Chapter 30 Surah Rum aayat 31-32: "This (Islam) is the right and true faith, but most people do not know. (Be steadfast on this) turning wholly and sincerely towards Allah Alone, and fear Him, and establish the Salat, and do not be like the mushriks, who have set up their separate creeds and divided themselves into sects, each sect rejoicing in what it has."
Allah says in the Holy Quran Chapter 23 Surah Mu’minoon verse 52-54: And you all belong to one and the same ummah, and I(Allah) am your Lord; so fear Me Alone! Yet afterwards the people divided themselves into different sects, and each sect rejoicing in what it has. Well, leave them deeply involved in their heedlessness up to an appointed time.
Whatever written of Truth and benefit is only due to Allah’s Assistance and Guidance, and whatever of error is of me. Allah Alone Knows Best and He is the Only Source of Strength.
Your brother and well wisher in Islam,