Lady Aisha Siddiqa (may Allah be pleased with her) narrates: The Prophet Muhammad (peace be upon him) used to remember Allah at all times.
(Imam Ibn Hibban, may Allah have mercy on him, says:) Lady Aisha (may Allah be pleased with her) saying: "The Prophet (peace be upon him) used to remember Allah at all times," by this she means the remembrance other than the Qur'an, because it is possible that by the words she used, she meant the Qur'an. However, the Prophet (peace be upon him) would not recite it in the state of major ritual impurity (janabah). In all other states, he would recite it.