Sahih al-Bukhari, Volume 1, Book 5, Hadith 252 (USC-MSA) ⓘ

Narrated Abu Ja`far: While I and my father were with Jabir bin `Abdullah, some people asked him about taking a bath. He replied, "A Sa` of water is sufficient for you." A man said, "A Sa` is not sufficient for me." Jabir said, "A Sa` was sufficient for one who had more hair than you and was better than you (meaning the Prophet)." And then Jabir (put on) his garment and led the prayer.

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مُحَمَّدٍ، قَالَ حَدَّثَنَا يَحْيَى بْنُ آدَمَ، قَالَ حَدَّثَنَا زُهَيْرٌ، عَنْ أَبِي إِسْحَاقَ، قَالَ حَدَّثَنَا أَبُو جَعْفَرٍ، أَنَّهُ كَانَ عِنْدَ جَابِرِ بْنِ عَبْدِ اللَّهِ هُوَ وَأَبُوهُ، وَعِنْدَهُ قَوْمٌ فَسَأَلُوهُ عَنِ الْغُسْلِ،‏.‏ فَقَالَ يَكْفِيكَ صَاعٌ‏.‏ فَقَالَ رَجُلٌ مَا يَكْفِينِي‏.‏ فَقَالَ جَابِرٌ كَانَ يَكْفِي مَنْ هُوَ أَوْفَى مِنْكَ شَعَرًا، وَخَيْرٌ مِنْكَ، ثُمَّ أَمَّنَا فِي ثَوْبٍ‏.‏