Guard strictly the (five obligatory) A.s-Salawãt (the prayers), especially the middle SaM! (i.e., the best prayer - Asr) .. . (V.2:238)

Hadith Number 4533

setting

Narrated `Ali (through two chains)

On the day of Al-Khandaq (the battle of the Trench). the Prophet (ﷺ) said, "They (i.e. pagans prevented us from offering the middle (the Best) Prayer till the sun had set. May Allah fill their graves, their houses (or their bodies) with fire."