What should I do about my religious fiancé, whom I fear might practice polygyny in the future, and should I discuss this matter with him again?

The questioner erred by asking her husband about his opinion on polygyny. She should not have rushed matters, but rather believed in Allah's divine decree and destiny. Polygyny is Allah's law and ruling, and it has many benefits, including fulfilling the need of women who are delayed in marriage. Blameworthy jealousy is that which prevents capable husbands from practicing polygyny. Praiseworthy jealousy is that which arises from suspicion, while detestable jealousy is that which arises without suspicion. The questioner is advised to marry this person of religious commitment and good character, for his religiosity will prevent him from injustice, Allah willing.