Jesus uses a question to answer John's disciples. They all knew that people do not mourn and fast at a wedding celebration. Jesus uses this proverb to show that his disciples do not mourn because he is still there with them. (See: [[rc://en/ta/man/translate/figs-rquestion]] and [[rc://en/ta/man/translate/writing-proverbs]])
This can be stated in active form. AT: "the bridegroom will not be able to be with them any longer" or "someone will take the bridegroom away from them" (See: [[rc://en/ta/man/translate/figs-activepassive]])
Jesus is probably referring to his own death, but this should not be made explicit here in the translation. To maintain the imagery of a wedding, it is best to just state that the bridegroom will not be there any longer.