The Prophet ﷺ used to remember Allah at all times.
كان النبي ﷺ يذكر الله على كل أحيانه.
No references are available.
Muslim narrated it in the Book of Menstruation (373), from the hadith of Ibn Abu Zaida, from his father, from Khalid bin Salama, from Bahi, from Urwa, from Ayesha, and she related the hadith.