Al-Baqarah: 83
{لَا تَعْبُدُونَ}
This is an informative statement in the sense of a prohibition, just as when you say to someone, "You go to so-and-so and tell him such-and-such," intending a command. This is more eloquent than an explicit command or prohibition, as it implies that the person is already hastening to comply and desist, such that one is merely reporting it. This is supported by the reading of ‘Abd Allāh and Ubayy: {لَا تَعْبُدُوا} (Do not worship). It is necessary to assume an implied "saying" (qawl), which is also indicated by His saying: {وَقُولُوا} (And say).
{وَبِالْوَالِدَيْنِ إِحْسَانًا}
It is either estimated as "You do good to the parents with goodness" (taḥsunūna bi-l-wālidayni iḥsānan) or "Do good" (aḥsinū). It is also said that it is the response to His saying: {وَإِذْ أَخَذْنَا مِيثَاقَ بَنِي إِسْرَائِيلَ} (And when We took the covenant of the Children of Israel), treating it as an oath, as if it were said: "And when We swore to them: You shall not worship..."
It is also said that the meaning is "that you do not worship" (an lā ta‘budū). When the an was omitted, the verb was put in the indicative mood (tarfa‘u), as in the verse: "O you who chide me for the heat of battle..." This is supported by the reading of ‘Abd Allāh: {أَنْ لَا تَعْبُدُوا}.
It is possible that the an is explanatory (mufassirah), or that the an with the verb acts as a substitute for the "covenant," as if it were said: "We took the covenant of the Children of Israel [to be] their monotheism." It is read with the tā’ (second person) as a narration of what they were addressed with, and with the yā’ (third person) because they are absent.
{حُسْنًا}
Meaning: "a saying that is good in itself," due to its extreme goodness. It is also read as ḥusnan and ḥusnā as an infinitive, like bushrā.
{ثُمَّ تَوَلَّيْتُمْ}
This follows the method of iltifāt (shifting from third to second person). It means: You turned away from the covenant and rejected it.
{إِلَّا قَلِيلًا مِنْكُمْ}
It is said these are those among them who accepted Islam.
{وَأَنْتُمْ مُعْرِضُونَ}
Meaning: You are a people whose habit is to turn away from covenants and to turn your backs.