Sunan at-Tirmithiy كتاب الصلاة باب ما جاء فى الترسل فى الأذان

حَدَّثَنَا أَحْمَدُ بْنُ الْحَسَنِ حَدَّثَنَا الْمُعَلَّى بْنُ أَسَدٍ حَدَّثَنَا عَبْدُ الْمُنْعِمِ هُوَ صَاحِبُ السِّقَاءِ قَالَ حَدَّثَنَا يَحْيَى بْنُ مُسْلِمٍ عَنِ الْحَسَنِ وَعَطَاءٍ عَنْ جَابِرِ بْنِ عَبْدِ اللَّهِ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ لِبِلاَلٍ يَا بِلاَلُ إِذَا أَذَّنْتَ فَتَرَسَّلْ فِى أَذَانِكَ وَإِذَا أَقَمْتَ فَاحْدُرْ وَاجْعَلْ بَيْنَ أَذَانِكَ وَإِقَامَتِكَ قَدْرَ مَا يَفْرُغُ الآكِلُ مِنْ أَكْلِهِ وَالشَّارِبُ مِنْ شُرْبِهِ وَالْمُعْتَصِرُ إِذَا دَخَلَ لِقَضَاءِ حَاجَتِهِ وَلاَ تَقُومُوا حَتَّى تَرَوْنِى.
The Messenger of God, peace and blessings of God be upon him, said to Bilāl, "Bilāl, when you are calling to prayer, proceed slowly, and when you are calling to the start of prayer (1), be prompt. And allow as much time between the call to prayer and the call to the start of prayer as one would need to finish eating, drinking, or answer the call of nature. And do not stand together to pray until you see me."  (1) The call to the start of prayer is a shorter and quicker version of the call to prayer that is said to let people know that the prayer is about to start.     Click on ḥadīth to read more