Waiting for prayer.
Waiting for prayer is a Sunnah that has a great virtue and entails great reward.
Abu Hurayrah (PBUH) said that the Prophet (PBUH) said,
“One is considered in prayer as long as he is waiting for prayer, and nothing but the prayer is preventing him from going to his family.”
(Al-Bukhāriy no. 659, Muslim no. 649)
Thus, Muslims are rewarded for waiting for prayer exactly as they are rewarded for the prayer itself.
Abu Hurayrah (ABPWH) said that the Prophet (PBUH) said:
“The angels pray for every one of you as long as he remains in the place in which he prayed and does not break his Wudū’ (ablution). The angles say, ‘O Allāh, forgive him. O Allāh, have mercy to him.’.”
(Al-Bukhāriy no. 659, Mulsim no. 649)
In another narration by Imām Muslim it says,
“… as long as he neither hurts anybody nor invalidates his ablution.”
(Muslim no. 649)
Thus, this reward is conditional, and the condition is to avoid doing any harm to others and to avoid invalidating Wudū’