وَلَا تَرْكَنُوٓا۟ إِلَى ٱلَّذِينَ ظَلَمُوا۟ فَتَمَسَّكُمُ ٱلنَّارُ
"Do not lean towards those who do wrong, or the Fire will touch you. You have no protectors besides God; and then you will not be helped."
Rukn: the corner of a building, its support, its firmest part. Rukūn — to rest on a thing, to lean on it, to incline towards it.
And the word had occurred earlier in this sūra: at 11/80 Lot said aw āwī ilā ruknin shadīd — "or could take shelter with some strong support".
The two uses stand in the same sūra, thirty-three verses apart, and are from the same root. I record this as my own reading: the sūra first shows a messenger looking for a support, and then says which support cannot be had.
The force of the verb must be recorded: what is forbidden is rukūn — that is, not "to become" but "to lean". The lexicographers explain it as the slightest inclination. And its counterpart is fa-tamassakumu'l-nār — "it will touch you", which is likewise the lightest verb of contact.
I record this as an observation, and it is not binding: the sentence chooses the least at both ends — the lightest inclination, the lightest touch. A measure is met with a measure.
ṭarafayi'l-nahār — the two ends of the day; zulafan mina'l-layl — the near hours of the night (ز-ل-ف: to draw near).
The exegetes differ over which prayers these times correspond to; no legal identification is made in this commentary. But similar descriptions of times were treated at al-Isrāʾ 17/78 (aqimi'l-ṣalāta li-dulūki'l-shamsi ilā ghasaqi'l-layl) and Ṭāhā 20/130 (wa sabbiḥ … qabla ṭulūʿi'l-shamsi wa qabla ghurūbihā).
The exegetes differ over the scope of the sentence — which bad deeds, on what conditions. No legal ruling is issued. But the word order must be recorded: the sentence comes immediately after the command about prayer and immediately after the prohibition of leaning towards those who do wrong. A possibility, that is, is placed after a prohibition.
ذَٰلِكَ ذِكْرَىٰ لِلذَّٰكِرِينَ — the same root twice: dhikrā and dhākirīn. A reminder is a reminder to one who remembers.
وَٱصْبِرْ فَإِنَّ ٱللَّهَ لَا يُضِيعُ أَجْرَ ٱلْمُحْسِنِينَ (115) — and the command to patience is the name of the thing shown again and again in the narrative section of the sūra. The pattern was treated at Yūsuf 12/90 (innahū man yattaqi wa yaṣbir fa-inna'llāha lā yuḍīʿu ajra'l-muḥsinīn).