Tafsir of Al-Anfal 8:44

{And when He showed them to you...} The two pronouns are objects. The meaning is: "And when He made you see them."

{...as few} This is in the accusative case as a state (ḥāl). He made them appear few in their eyes to confirm the vision of the Messenger of Allah (ﷺ), so that they might witness what he had informed them of, thereby increasing their certainty, diligence, and steadfastness.

Ibn Mas‘ūd (may Allah be pleased with him) said: "They were made to appear so few in our eyes that I said to a man beside me, 'Do you see them as seventy?' He replied, 'I see them as a hundred.' We then captured a man from them and asked, 'How many were you?' He said, 'Two thousand.'"

{...and He made you appear few in their eyes} ...until one of them said, "They are merely a meal for a slaughter-camel."

If you ask: The purpose of making the disbelievers appear few in the eyes of the believers is clear, but what is the purpose of making the believers appear few in the eyes of the disbelievers?

I say: He made them appear few in their eyes before the encounter, then made them appear numerous after it began, so that the disbelievers would become emboldened and indifferent toward them. Then, when the multitude suddenly confronted them, they would be stunned, filled with awe, and their strength would be broken when they saw what was not in their calculations or estimations. This is the meaning of His saying: {They saw them as twice their number, with their own eyes} (Al ‘Imrān: 13). It was also so that they would not prepare for them, and to make the proof against them greater by clarifying the manifest sign through their fewness at first and their multitude at the end.

If you ask: By what means do they see the many as few?

I say: By Allah concealing some of them from their sight with a veil, or by creating in their eyes a perception that makes the many appear small, just as He created in the eyes of the cross-eyed a condition where they see one thing as two. It was said to a cross-eyed man: "The cross-eyed person sees one thing as two." There was a single rooster in front of him, so he said, "Why do I not see these two roosters as four?"

{O you who have believed, when you encounter a company, stand firm and remember Allah much that you may succeed. And obey Allah and His Messenger, and do not dispute and [thus] lose courage and [then] your strength would depart; and be patient. Indeed, Allah is with the patient.}