Sahih Bukhari
Actions while Praying
Volume: 002 / Book Number: 022 / Hadith Number: 292
Narrated Zaid bin Arqam:
In the life-time of the Prophet 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.