فَلْيَنظُرِ ٱلْإِنسَـٰنُ مِمَّ خُلِقَ
The فَ at the head states the consequence of the previous verse: since there is a watcher over him, then let him look. The proof comes after the ruling.
The verb has come with the lām of command: li- + imperfect = a command addressed to the third person. English has no exact equivalent; it is rendered with "let him look".
This has a consequence: the address is indirect. It does not say "look", it says "let man look". The one addressed is not called upon directly; a kind of general ruling is set up, and the hearer finds himself inside that ruling. The Qurʾān uses this pattern often where it calls to reflection: "Let man look at his food" (ʿAbasa 80/24); "Let them look at the camel, how it was created" (al-Ghāshiya 88/17).
Root: ن-ظ-ر. Not merely to see; to look attentively, to turn the eye upon something and dwell on it. Naẓariyya (theory), manẓara (a view, a scene) and intiẓār (waiting — the eye left on the road) are from the same root; Turkish has borrowed all of them.
The Qurʾān also uses the verb raʾā for "to see". The difference between naẓar and ruʾya is this: naẓar is the act of looking and may not end in seeing; ruʾya is the seeing itself. Here the verse commands not an outcome but an operation: turn and look.
In Arabic, when the interrogative mā comes after a preposition its alif drops: ʿan mā → ʿamma (al-Nabaʾ 78/1); fī mā → fīma; li mā → lima; min mā → mimma. This rule serves to tell the interrogative mā apart from the relative mā — because when it is the relative the alif does not drop (mimmā).
It looks like a small rule of spelling, but its function is large: that the verse is written mimma (without the alif) settles that the sentence is a question. Not "from the thing he was created from", but "from what he was created".
The verse does not say "let man look where he is going". It says let him look at "what he was created from". That is, the looking is not forward but back.
The reason for this is the subject of the dispute. The objection of those addressed was about the resurrection: "When we have become dust and are scattered, shall we really be in a new creation?" (al-Raʿd 13/5; the like in Sabaʾ 34/7, Qāf 50/3). That is, the objection was about the possibility of a future event.
Against this objection the Qurʾān regularly uses the same method: it does not argue about the future, it takes you back to the past. Because for a thing that has happened once to happen a second time is, in point of possibility, nothing new.
The verse is the shortest expression of this method: it does not give the answer, it shows where the answer is. It says "Look".