Is it permissible for a marriage to take place and for the uncircumcised suitor to consummate the marriage with his fiancée, knowing that he is a Muslim and his family is unaware of this?

It is permissible for an uncircumcised man to marry and to engage in conjugal relations after the marriage contract. He is obligated to be circumcised if possible, without harm. Circumcision is waived for a Muslim if he fears for himself, according to Ibn Qudamah: "If an elderly man embraces Islam and fears for himself from circumcision, it is waived for him." However, if he is safe, it becomes obligatory, as Imam Ahmad said: "It is more beloved to me that he purifies himself because of the hadith: 'Ibrahim was circumcised when he was eighty years old.' Allah Almighty said: '{the religion of your father Abraham}'."