By Him who took his soul ﷺ, he did not die until most of his prayer was performed while sitting, and the dearest of deeds to him was the righteous deed that a servant maintains consistently, even if it is small.
والذي ذهب بنفسه ﷺ ما مات حتى كان أكثر صلاته وهو جالس، وكان أحب الأعمال إليه العمل الصالح الذي يدوم عليه العبد، وإن كان يسيرا.
Nasai (1655), Ibn Majah (1225, this being his wording), and Ahmad (26599) all narrated it, and Ibn Hibban (2507) graded it sahih, all of them through various routes from Abu Ishaq, from Abu Salama bin Abdul-Rahman, from Umm Salama, and he mentioned it, and its isnad is sahih.Something with a similar meaning was narrated from Abu Hurairah, who said, the Messenger of Allah ﷺ said, "Take on only as much work as you can bear, for the best deed is the one done most consistently, even if it is little." Ibn Majah (4240) and Ahmad (8600) narrated it, both through the route of Ibn Lahia, who said, Abdul-Rahman Araj narrated to us, saying, I heard Abu Hurairah say, and he mentioned it. There is well known criticism of Ibn Lahia, and this narration is not among those he transmitted through Abadila and Qutayba bin Saeed.