and the call to prayer is made for them; whoever performs voluntary prayers in the mosque during the day does well, for Mālik did not regard the daytime in the same way as the night, and no adhān is legislated for any of the supererogatory or Sunnah prayers.
The Messenger of Allah ﷺ used to offer voluntary prayers on his mount and even perform witr there, whereas the obligatory prayers he would perform on the ground. This practice refutes the opinion of those who consider witr obligatory.
According to Mālik, a person who is walking may not perform supererogatory prayer—whether facing the qiblah or otherwise—and neither may someone lying on his back or side, except when illness necessitates it. It is permissible, however, for both the able-bodied and the infirm to pray a nafl prayer while seated; yet whoever is able to stand but chooses to pray sitting receives only half the reward of one who stands. The manner in which the seated worshipper sits, and everything else related to his posture, follows the same rulings as the prayer of the sick, as has already been mentioned in the chapter on the prayer of the sick.
It is recommended for a person praying a voluntary prayer while seated that, when he nears the point of bowing, he should stand, recite about thirty verses—or thereabouts—and then bow from the standing position; if he does not do so, there is no blame.
Whoever breaks off a voluntary prayer without a valid excuse must make it up according to Mālik, but if he is interrupted by an excuse or loses his state of purity, nothing is required of him.