Ibn Majah

1؎: Idle and unnecessary conversations after the ‘Isha prayer are disliked (makruh), and the reason for this dislike is that perhaps the night may pass on and one may not wake up for the Tahajjud prayer, or may not be able to perform the Fajr prayer at its earliest time and in congregation. Another reason is that in sleep, it is as if a person dies, so it is better that the conclusion (end) be upon worship, not upon worldly matters. However, if there are necessary matters related to religion or the world, then it is permissible to discuss them. In another hadith, it is mentioned that the Prophet (sallallahu alayhi wa sallam) spoke with Abu Bakr and ‘Umar (radi Allahu anhuma) after ‘Isha regarding the affairs of the Muslims.