At-Tawba 9:40

If you do not support the Prophet, Allah has already supported him when the disbelievers forced him out; when he was second of the two[38] in the cave – saying to his companion, “Do not grieve; Allah is with us.” Thereupon Allah sent down His tranquility upon him, supported him with soldiers that you did not see[39], and rendered the word of the disbelievers[40] the lowest, whereas the Word of Allah[41] is supreme. And Allah is All-Mighty, All-Wise.

[38] The second was his companion, Abu Bakr.
[39] Angels came to the Prophet’s aid in the small cave.
[40] i.e., their claims and slogans of disbelief.
[41] i.e., "La ilaha illa Allah" (There is no true deity except Allah).

If you do not aid him [i.e., the Prophet (ﷺ)] - Allāh has already aided him when those who disbelieved had driven him out [of Makkah] as one of two,[476] when they were in the cave and he [i.e., Muḥammad (ﷺ)] said to his companion, "Do not grieve; indeed Allāh is with us." And Allāh sent down His tranquility upon him and supported him with soldiers [i.e., angels] you did not see and made the word[477] of those who disbelieved the lowest,[478] while the word of Allāh[479] - that is the highest. And Allāh is Exalted in Might and Wise.

[476] The second was his companion, Abū Bakr.
[477] i.e., their claims and slogans.
[478] i.e., degraded and dishonored.
[479] "Lā ilāha ill-Allāh" ("There is no deity except Allāh").

40. If you help him (Muhammad صلى الله عليه وسلم) not (it does not matter), for Allâh did indeed help him when the disbelievers drove him out, the second of the two; when they (Muhammad صلى الله عليه وسلم and Abu Bakr رضي الله عنه) were in the cave, he (صلى الله عليه وسلم) said to his companion (Abu Bakr رضي الله عنه): "Be not sad (or afraid), surely Allâh is with us." Then Allâh sent down His Sakînah (calmness, tranquillity, peace) upon him, and strengthened him with forces (angels) which you saw not, and made the word of those who disbelieved the lowermost, while the Word of Allâh that became the uppermost; and Allâh is All-Mighty, All-Wise.

If ye help him not, still Allah helped him when those who disbelieve drove him forth, the second of two; when they two were in the cave, when he said unto his comrade: Grieve not. Lo! Allah is with us. Then Allah caused His peace of reassurance to descend upon him and supported him with hosts ye cannot see, and made the word of those who disbelieved the nethermost, while Allah's Word it was that became the uppermost. Allah is Mighty, Wise.