Ibn Hishām said (1): “Some scholars told me that al-Ḥasan ibn Abī al-Ḥasan al-Baṣrī related: ‘The Messenger of Allah ﷺ and Abū Bakr reached the cave by night. Abū Bakr entered before the Messenger of Allah ﷺ, feeling his way around to see whether a beast or a serpent might be inside, so that he could shield the Messenger of Allah ﷺ with his own self.’”
This report is broken in its chain at both ends.

Abū al-Qāsim al-Baghawī said: “Dāwūd ibn ʿAmr al-Ḍabbī narrated to us; Nāfiʿ ibn ʿUmar al-Jumaḥī narrated from Ibn Abī Mulaykah that when the Prophet ﷺ set out with Abū Bakr for Thawr, Abū Bakr would sometimes walk in front of the Prophet and at other times behind him. The Prophet ﷺ asked him about this, and he replied, ‘When I am behind you I fear that you may be attacked from the front, and when I am in front of you I fear an attack from behind.’

“When they reached the cave of Thawr, Abū Bakr said, ‘Stay where you are until I put my hand inside, feel it, and search it. If there is any creature in it, it will strike me before it reaches you.’”

Nāfiʿ added: “It reached me that there was a hole in the cave, so Abū Bakr plugged it with his foot, fearing that some creature might come out of it and harm the Messenger of Allah ﷺ.”
This report is mursal, and we have cited other supporting narrations in the biography of the Truthful One, Abū Bakr ﵁ (2).

Al-Bayhaqī said (3): “Abū ʿAbd Allah al-Ḥāfiẓ dictated to us; Abū Bakr Aḥmad ibn Isḥāq informed us; Mūsā ibn al-Ḥasan ibn (4) ʿAbbād narrated to us; ʿAffān ibn Muslim narrated to us; al-Sarī ibn Yaḥyā narrated to us; Muḥammad ibn Sīrīn said:

‘During the caliphate of ʿUmar, some men seemed to give ʿUmar precedence over Abū Bakr. When this reached ʿUmar he said, “By Allah, one night of Abū Bakr is better than the whole household of ʿUmar, and one day of Abū Bakr is better than the whole household of ʿUmar. The Messenger of Allah ﷺ set out for the cave one night with Abū Bakr, and Abū Bakr kept walking a while in front of him and a while behind him.

“The Messenger of Allah ﷺ noticed and said:
‘O Abū Bakr, why do you walk sometimes in front of me and sometimes behind me?’
He replied, ‘O Messenger of Allah, when I remember those pursuing us I walk behind you; when I think of an ambush I walk in front of you.’

“The Prophet said, ‘O Abū Bakr, if something were to happen, would you wish it to befall you instead of me?’
He answered, ‘Yes, by the One who sent you with the truth, there is no calamity I would not prefer to bear in your stead.’

“When they reached the cave Abū Bakr said, ‘Stay where you are, O Messenger of Allah, until I make sure it is safe for you.’ He went in and inspected it; when he reached the upper part he recalled that he had not yet checked the holes, so he said, ‘Stay where you are, O Messenger of Allah, until I examine them.’ He went back in, inspected them, and then said, ‘Come down, O Messenger of Allah.’ So he did.”

ʿUmar concluded, “By Him in whose hand is my soul, that single night is better than the whole household of ʿUmar.”’

Al-Bayhaqī also transmitted it through another chain from ʿUmar, in which it states that Abū Bakr would at times walk in front of the Messenger of Allah ﷺ… (5)