Is it permissible for a Christian who embraced Islam to marry more than one wife?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

If the said person has embraced Islam, then he has the same rights as Muslims because he is considered to be one of them; the fact that he was a non-Muslim or atheist before is not a problem because [embracing] Islam wipes out previous sins. Allaah Says (what means): {Say to those who have disbelieved [that] if they cease, what has previously occurred will be forgiven for them. But if they return [to hostility], then the precedent of the former [rebellious] peoples has already taken place.}[Quran 8:38]. Therefore, there is no harm for the person whom you asked about to marry up to four wives, provided he is financially solvent, physically able and just, as Allaah Says (what means): {And if you fear that you will not deal justly with the orphan girls, then marry those that please you of [other] women, two or three or four. But if you fear that you will not be just, then [marry only] one.}[Quran 4:3].

Allaah Knows best.