Narrated ‘Zaid bin Arqam: In the lifetime of the Prophet (pbuh) we used to speak while praying, and one of us would tell his needs to his companions, till the verse,
“(Surah Baqarah 2:238) was revealed”
Guard strictly (five obligatory) As-Salawat (the prayers) especially the Middle Salah (Asr Salah). And stand before Allah with obedience
After that we were ordered to remain silent while praying.
Sahih al-Bukhari, Actions while Praying Book 21, Hadith 4