What does "on his face" mean in Sahih al-Bukhari 27?

Question

Sahih al-Bukhari 27:

Narrated Sa'd:

Allah's Messenger (ﷺ) distributed (Zakat) amongst (a group of) people while I was sitting there but Allah's Messenger (ﷺ) left a man whom I thought the best of the lot. I asked, "O Allah's Messenger (ﷺ)! Why have you left that person? By Allah I regard him as a faithful believer." The Prophet (ﷺ) commented: "Or merely a Muslim." I remained quiet for a while, but could not help repeating my question because of what I knew about him. And then asked Allah's Messenger (ﷺ), "Why have you left so and so? By Allah! He is a faithful believer." The Prophet (ﷺ) again said, "Or merely a Muslim." And I could not help repeating my question because of what I knew about him. Then the Prophet (ﷺ) said, "O Sa'd! I give to a person while another is dearer to me, for fear that he might be thrown on his face in the Fire by Allah."

What does the noun phrase "on his face" mean in this Hadith?

Answer 1

First of all the statement:

for fear that he might be thrown on his face in the Fire by Allah

in this hadith is a rather (bad) literal translation of:

خَشْيَةَ أَنْ يَكُبَّهُ اللَّهُ فِي النَّارِ

The verb:

كَبَّ

in Arabic means:

turned it over (or simply moved to, changed the position to)

For example a vessel or pot that was standing on the bottom and was turned over to the open upper side. To let liquid of fluid come out. Therefore another common translation or synonym would be pour as this verb is usually used to express pouring something.

But the meaning of this statement simply is:

for fear that Allah may throw him in the Hellfire.

Imam an-Nawawi in his commentary of Sahih Muslims of this version of the hadith -see here in Arabic- explains it as follows:
^{In the following I'm translating from Arabic language, as these translations are of my own take them carefully!}

معناه : إني أعطي ناسا مؤلفة ، في إيمانهم ضعف ، لو لم أعطهم كفروا ، فيكبهم الله في النار ، وأترك أقواما هم أحب إلي من الذين أعطيتهم ، ولا أتركهم احتقارا لهم ، ولا لنقص دينهم ، ولا إهمالا لجانبهم ، بل أكلهم إلى ما جعل الله في قلوبهم من النور والإيمان التام ، وأثق بأنهم لا يتزلزل إيمانهم لكماله .
Has the Meaning: I give people who are composed, who have weakness in their faith, if I did not give they would disbelief, Allah will pour them into hellfire, and I leave people who are dearer to me than those whom I have given, and I do not leave them with contempt for them, nor for lack of their religion, nor neglect of their side, but leave them to what Allah Has made their hearts are full of light and faith, and I trust that their faith does not waver to its perfection.