بُلُوغُ الْمَرَامِ
Bulugh al-Maram 197
The Book of Prayer
وَعَنْ جَابِرٍ - رضى الله عنه - أَنَّ رَسُولَ اَللَّهِ - صلى الله عليه وسلم -قَالَ لِبِلَالٍ : { إِذَا أَذَّنْتَ فَتَرَسَّلْ , وَإِذَا أَقَمْتُ فَاحْدُرْ , وَاجْعَلْ بَيْنَ أَذَانِكَ وَإِقَامَتِكَ قَدْرَ مَا يَفْرُغُ اَلْآكِلُ مِنْ أَكْلِهِ } اَلْحَدِيثَ . رَوَاهُ اَلتِّرْمِذِيُّ وَضَعَّفَهُ . [1] .
Narrated Jabir (RA): Allah's Messenger (ﷺ) said to Bilal, "When you announce the Adhan, utter deliberately and when you pronounce the Iqamah utter quickly, and leave between your Adhan and your Iqamah time for one who is eating to finish his food." [Reported by at-Tirmidhi who graded it Da'if (weak)].
Sunnah.com reference: Book 2, Hadith 59