Indeed, it is a true dream, Allah Willing! Go and teach these words to Bilāl, and let him make the call to prayer with them, as his voice is more melodious than yours

عن عبد الله بن زيد رضي الله عنه قال: لَمَّا أَمَرَ رسول الله صلى الله عليه وسلم بِالنَّاقُوسِ يُعْمَلُ لِيُضْرَبَ بِهِ لِلنَّاسِ لِجَمْعِ الصلاة طاف بي وأنا نائم رجل يحمل ناقوساً في يده، فقلت: يا عبد الله أَتَبِيعُ الناقوس؟ قال: وما تصنع به؟ فقلت: ندعو به إلى الصلاة، قال: أَفَلَا أَدُلُّكَ عَلَى مَا هُوَ خَيْرٌ مِنْ ذَلِكَ؟ فقلت له: بلى، قال: فقال: تقول: الله أكبر، الله أكبر، الله أكبر، الله أكبر، أشهد أن لا إله إلا الله، أشهد أن لا إله إلا الله، أشهد أن محمدا رسول الله، أشهد أن محمدا رسول الله، حيَّ على الصلاة، حيَّ على الصلاة، حيَّ على الفلاح، حيَّ على الفلاح، الله أكبر، الله أكبر، لا إله إلا الله، قال: ثُمَّ اسْتَأْخَرَ عَنِّي غَيْرَ بعيد، ثم قال: وتقول إِذَا أَقَمْتَ الصَّلَاةَ: الله أكبر الله أكبر، أشهد أن لا إله إلا الله، أشهد أن محمدًا رسول الله، حيَّ على الصلاة، حيَّ على الفلاح، قَدْ قَامَتِ الصَّلَاةُ، قد قامتِ الصلاة، الله أكبر الله أكبر، لا إله إلا الله، فلما أصبحت، أتيتُ رسول الله صلى الله عليه وسلم ، فأخبرته، بما رأيتُ فقال: «إِنَّهَا لَرُؤْيَا حَقٌّ إِنْ شَاءَ اللَّهُ، فَقُمْ مَعَ بِلَالٍ فَأَلْقِ عَلَيْهِ مَا رَأَيْتَ، فَلْيُؤَذِّنْ بِهِ، فإنه أَنْدَى صوتا منك» فقمتُ مع بلال، فَجَعَلْتُ أُلْقِيهِ عَلَيْهِ، وَيُؤَذِّنُ بِهِ، قَالَ: فَسَمِعَ ذَلِكَ عُمَرُ بنُ الخَطَّاب، وهو في بيته فخرج يَجُرُّ رِدَاءَهُ، ويقول: وَالَّذِي بَعَثَكَ بِالحَقِّ يَا رَسُولَ اللَّهِ، لقد رأيتُ مثل ما رأى، فقال رسول الله صلى الله عليه وسلم : «فَلِلَّهِ الحَمْدُ».

‘Abdullāh ibn Zayd (may Allah be pleased with him) reported: When the Messenger of Allah (may Allah's peace and blessings be upon him) ordered that a bell be rung to gather the people for prayer, I saw a dream where a man was going around carrying a bell. I said to him: "O slave of Allah, are you selling this bell?" He said: "What will you do with it?" I said: "We will call the people to prayer." He said: "Shall I direct you to what is better than it?" I replied: ‘Yes.’ He said: "Say: 'Allah is the Greatest (four times); I bear witness that there is no god but Allah (twice); I bear witness that Muhammad is the Messenger of Allah (twice); come to prayer (twice); come to success (twice); Allah is the Greatest (twice); there is no god but Allah.'" Then he stood close behind me and said: "Then, when the prayer is about to begin, say: 'Allah is the Greatest (twice); I bear witness that there is no god but Allah; I bear witness that Muhammad is the Messenger of Allah; come to prayer; come to success; the prayer is about to commence (twice) [In another narration: “And if it is the Fajr prayer, say: ‘prayer is better than sleep (twice).’”]; Allah is the Greatest (twice); there is no god but Allah.'" When I woke up, I went to the Messenger of Allah (may Allah's peace and blessings be upon him) and informed him of my dream. He said: ‘Indeed, it is a true dream, Allah Willing! Go and teach these words to Bilāl, and let him make the call to prayer with them, as his voice is more melodious than yours.’ So I took Bilāl and taught him those words, and he made the call to prayer therewith. ‘Umar ibn al-Khattāb heard it while at home, and so he came out dragging his garment and saying: "By the One Who sent you with the truth, O Messenger of Allah, I saw the same dream that he saw!" Thereupon, the Prophet (may Allah's peace and blessings be upon him) said: "All praise is due to Allah."

Source · Narrated by Abu Daoud - Narrated by Ahmad - Ad-Daarimi

From the Hadith Encyclopedia (hadeethenc.com).