Is it a sin to refuse marriage proposals from those who have come to ask for my hand, because they do not possess the scientific mindset that I aspire to have in my life partner, knowing that I wish to dedicate myself to study and to calling people to Allah, and I fear that I will not find someone worthy of being a father to my children?

If a woman is proposed to by a man of religious commitment and good character, but she does not feel comfortable with him, she is not to be blamed for rejecting him. This is because the marriage contract is a serious matter and must be surrounded by factors that ensure its success. While religious commitment and good character are important, a woman may also consider other matters such as customs, intellectual compatibility, financial status, and beauty, as mentioned in the Sunnah of the Prophet, provided these are not the primary basis. However, one should not abstain from marriage for any reason, as it is the practice of the Prophets and Messengers, and the Prophet, peace and blessings be upon him, commanded and encouraged it.