[Machine] We used to sit with Abi Zuhair Al-Namiri, who was one of the Companions of the Prophet ﷺ . He would speak and tell stories well. When someone among us would make a supplication, he would end it with "Ameen". For in supplication, "Ameen" is like a seal on a document. Abu Zuhair said, "I will tell you about this." One night, we went out with the Messenger of Allah ﷺ and walked until we came across a man in a tent who was extremely earnest in his request. The Messenger of Allah ﷺ stood there and listened to him. Then the Messenger of Allah ﷺ said, "It is obligatory (for the supplication to be answered) if he ends it (with 'Ameen')." A man from the people asked the Messenger of Allah ﷺ , "What is it that makes it obligatory, O Messenger of Allah?" He replied, "If he ends it with 'Ameen', then it is obligatory." The man who asked the Messenger of Allah ﷺ turned away and said, "End it, O so and so, with 'Ameen' and take glad tidings."  

كُنَّا نَجْلِسُ إِلَى أَبِي زُهَيْرٍ النُّمَيْرِيِّ وَكَانَ مِنْ أَصْحَابِ النَّبِيِّ ﷺ فَيَتَحَدَّثُ فَيُحْسِنُ الْحَدِيثَ فَإِذَا دَعَا الرَّجُلُ مِنَّا بِدُعَاءٍ قَالَ اخْتِمُوهُ بِآمِينَ فَإِنَّ آمِينَ فِي الدُّعَاءِ مِثْلُ الطَّابَعِ عَلَى الصَّحِيفَةِ قَالَ أَبُو زُهَيْرٍ وَأُخْبِرُكُمْ عَنْ ذَلِكَ خَرَجْنَا مَعَ رَسُولِ اللهِ ﷺ ذَاتَ لَيْلَةٍ نَمْشِي فَأَتَيْنَا عَلَى رَجُلٍ فِي خَيْمَةٍ قَدْ أَلْحَفَ فِي الْمَسْأَلَةِ فَوَقَفَ رَسُولُ اللهِ ﷺ يَسْتَمِعُ مِنْهُ فَقَالَ رَسُولُ اللهِ ﷺ «أَوْجَبَ إِنْ خَتَمَ» فَقَالَ لَهُ رَجُلٌ مِنَ الْقَوْمِ بِأَيِّ شَيْءٍ يَخْتِمُ يَا رَسُولَ اللهِ؟ قَالَ «بِآمِينَ إِنْ خَتَمَ بِآمِينَ فَقَدْ أَوْجَبَ» فَانْصَرَفَ الرَّجُلُ الَّذِي سَأَلَ رَسُولَ اللهِ ﷺ فَقَالَ «اخْتِمْ يَا فُلَانُ بِآمِينَ وَأَبْشِرْ»