[سُورَةٌ أَنزَلْنَـهَا]

(A Surah which We have sent down) Here Allah is pointing out the high esteem in which He holds this Surah, which is not to say that other Surahs are not important.

[وَفَرَضْنَـهَا]

(and which We have enjoined,) Mujahid and Qatadah said, "This means: We have explained what is lawful and unlawful, commands and prohibitions, and the prescribed punishments.'' Al-Bukhari said, "Those who read it: Faradnaha, say that it means: "We have enjoined them upon you and those who come after you.''

[وَأَنزَلْنَا فِيهَآ ءَايَـتٍ بَيِّنَـتٍ]

(and in it We have revealed manifest Ayat,) means, clearly explained,

[لَعَلَّكُمْ تَذَكَّرُونَ]

(that you may remember.)