Sunan an-Nasa'i, Book 5, Hadith 14 (In-Book) ⓘ

It was narrated from Ibn Muhairiz that a man from Banu Kinanah who was called Al-Mukhdaji heard a man in Ash-Sham, who was known as Abu Muhammad, saying that Witr was obligatory. Al-Mukhdaji said: "In the morning I went to 'Ubadah bin As-Samit, and I met him while he was on his way to the Masjid. I told him what Abu Muhammad said, and 'Ubadah said: 'Abu Muhammad is wrong. I heard the Messenger of Allah say: 'Five prayers are those that Allah has decreed for (His) slaves, whoever does them, and does not neglect any of them out of disregard toward them, will have a promise from Allah that He will admit him to Paradise. And whoever does not to them will have no such promise from Allah; if He wills he will punish him and if He wills He will admit him to Paradise.

أَخْبَرَنَا قُتَيْبَةُ، عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، عَنْ مُحَمَّدِ بْنِ يَحْيَى بْنِ حَبَّانَ، عَنِ ابْنِ مُحَيْرِيزٍ، أَنَّ رَجُلاً، مِنْ بَنِي كِنَانَةَ يُدْعَى الْمُخْدَجِيَّ سَمِعَ رَجُلاً، بِالشَّامِ يُكْنَى أَبَا مُحَمَّدٍ يَقُولُ الْوِتْرُ وَاجِبٌ ‏.‏ قَالَ الْمُخْدَجِيُّ فَرُحْتُ إِلَى عُبَادَةَ بْنِ الصَّامِتِ فَاعْتَرَضْتُ لَهُ وَهُوَ رَائِحٌ إِلَى الْمَسْجِدِ فَأَخْبَرْتُهُ بِالَّذِي قَالَ أَبُو مُحَمَّدٍ فَقَالَ عُبَادَةُ كَذَبَ أَبُو مُحَمَّدٍ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ ‏ "‏ خَمْسُ صَلَوَاتٍ كَتَبَهُنَّ اللَّهُ عَلَى الْعِبَادِ مَنْ جَاءَ بِهِنَّ لَمْ يُضَيِّعْ مِنْهُنَّ شَيْئًا اسْتِخْفَافًا بِحَقِّهِنَّ كَانَ لَهُ عِنْدَ اللَّهِ عَهْدٌ أَنْ يُدْخِلَهُ الْجَنَّةَ وَمَنْ لَمْ يَأْتِ بِهِنَّ فَلَيْسَ لَهُ عِنْدَ اللَّهِ عَهْدٌ إِنْ شَاءَ عَذَّبَهُ وَإِنْ شَاءَ أَدْخَلَهُ الْجَنَّةَ ‏" ‏ ‏.‏