The Sufficient (Vol 1) · Hadith 460 (#Ḥadīth #4)
Chapter 6 | The Issue that even if only two people would remain on earth one of them would certainly be the Imam, the person with divine authority
4ـ عِدَّةٌ مِنْ أَصْحَابِنَا عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ الْبَرْقِيِّ عَنْ عَلِيِّ بْنِ إِسْمَاعِيلَ عَنِ ابْنِ سِنَانٍ عَنْ حَمْزَةَ بْنِ الطَّيَّارِ قَالَ سَمِعْتُ أَبَا عَبْدِ الله يَقُولُ لَوْ لَمْ يَبْقَ فِي الارْضِ إِلا اثْنَانِ لَكَانَ أَحَدُهُمَا الْحُجَّةَ أَوْ الثَّانِي الْحُجَّةَ. الشَّكُّ مِنْ أَحْمَدَ بْنِ مُحَمَّدٍ.
4. A number of our people has narrated from Ahmad ibn Muhammad al-Barqi from Ali ibn Isma‘il from ibn Sinan from Hamza ibn al-Tayyar who has said the following. “I heard Imam abu ‘Abdallah saying, ‘Would there remain on earth no one except two people one of them will be the person with Divine authority or the second one will be the person with Divine authority (uncertainty is from the narrator).”
Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).