Abu Sa'eed Al-Khudri said: "The Messenger of Allah (ﷺ) said: 'While I was sleeping, I saw the people being shown to me, and they were wearing shirts. Some reached the breast and some reached lower than that. And 'Umar bin Al-Khattab was shown to me, and he was wearing a shirt that he was dragging;' They said: 'How do you interpret that, O Messenger of Allah?' He said: 'The religion.'"
Source: sunnah.com
Other translations
Arabic
أَخْبَرَنَا مُحَمَّدُ بْنُ يَحْيَى بْنِ عَبْدِ اللَّهِ قَالَ حَدَّثَنَا يَعْقُوبُ بْنُ إِبْرَاهِيمَ بْنِ سَعْدٍ قَالَ حَدَّثَنَا أَبِي عَنْ صَالِحِ بْنِ كَيْسَانَ عَنْ ابْنِ شِهَابٍ قَالَ حَدَّثَنِي أَبُو أُمَامَةَ بْنُ سَهْلٍ أَنَّهُ سَمِعَ أَبَا سَعِيدٍ الْخُدْرِيَّ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ بَيْنَا أَنَا نَائِمٌ رَأَيْتُ النَّاسَ يُعْرَضُونَ عَلَيَّ وَعَلَيْهِمْ قُمُصٌ مِنْهَا مَا يَبْلُغُ الثُّدِيَّ وَمِنْهَا مَا يَبْلُغُ دُونَ ذَلِكَ وَعُرِضَ عَلَيَّ عُمَرُ بْنُ الْخَطَّابِ وَعَلَيْهِ قَمِيصٌ يَجُرُّهُ قَالَ فَمَاذَا أَوَّلْتَ ذَلِكَ يَا رَسُولَ اللَّهِ قَالَ الدِّينَ
sunnah.com