Hawzah News Agency – The merciful prophet of Islam, peace be upon him and his household says:

لا تُكثِرُوا الكلامَ بغَيرِ ذِكرِ اللَّهِ؛ فإنَّ كَثرَةَ الكلامِ بغَيرِ ذِكرِ اللَّهِ قَسوَةُ القَلبِ، إنّ أبعَدَ الناسِ مِن اللَّهِ القَلبُ القاسي.

'Do not speak excessively without the remembrance of Allah, for excessive speech devoid of the remembrance of Allah hardens the heart. The farthest of people from Allah are the hard-hearted.'

Source: Amali al-Tusi, v. 3, p. 1