Bismillah Walhamdulillah Was Salaatu Was Salaam ‘ala Rasulillah
Narrated Zaid bin Arqam (Radi-Allahu ‘anhu):
In the life-time of the Prophet (Sallallahu ‘Alaihi Wa Sallam) we used to speak while praying, and one of us would tell his needs to his companions, till the verse, ‘Guard strictly your prayers (2.238)’ was revealed. After that we were ordered to remain silent while praying.
Bukhari Vol. 2 : No. 292