It has been clarified in the Qur’an that Allah Almighty spoke to some Prophets directly as well as through the Angel Jibril. As Muslims, we should believe that Allah talks to whom He wishes with the way He Almighty wishes. Such issues are part of the Unseen or ghaib for which we are ordered to believe as revealed by Allah without pondering over the ‘how’ mechanisms.
Sheikh Muhammad Nur Abdullah, ISNA President and Member of the Fiqh Council of North America, states the following: “Allah spoke to some Prophets directly such as Prophet Musa (peace be upon him) and Prophet Muhammad (peace be upon him). As for Prophet Muhammad, Allah spoke to him on the journey of Al-Mi`raj.
Allah also sent down revelations through Angel Jibril, peace be upon him. Prophet Muhammad, for example, used to receive the Qur’an through Jibril, memorize and then deliver to other companions, some of who used to write them down. Allah promised Prophet Muhammad to give him the sharpest memory that allows him to remember the Qur’an, besides Jirbril used to review it with him.”