Tafsir of Al-Anbiya' 21:51

"His guidance [rushd]": This refers to being guided toward the paths of righteousness. Allah the Exalted says: "And test the orphans until they reach marriageable age; then if you perceive in them sound judgment [rushd]..." (An-Nisa: 6). It is also read as rushd and rashad, like ‘adam and ‘udm. The meaning of attributing it to him is that it was a guidance befitting him, a guidance of great significance.

"Before": That is, before Moses and Aaron, peace be upon them. The meaning of "We knew him" (in the context of giving him guidance) is that Allah knew of him wondrous states, marvelous secrets, and qualities that He approved of and praised, until He deemed him worthy of His intimate friendship (khullah) and sincere devotion. This is like saying about the best of people, "I know so-and-so"; your statement here encompasses all his virtuous attributes.

"When he said to his father and his people, 'What are these statues...'" This phrase either relates to "We gave," or to "his guidance," or to an omitted element—meaning: "Recall, from the times of his guidance, this specific time."

"What are these statues": He feigns ignorance and plays the fool to belittle their gods and diminish their status, despite his full knowledge of how they venerated and exalted them. He did not provide an object for "devoted" (‘akifun), treating it as an intransitive verb, as if you were to say, "They are devoted to them" or "They are standing for them." If you ask: "Why was it not said ‘alayha ‘akifun (devoted upon them), as in the verse: 'They were devoted to idols of theirs' (Al-A'raf: 138)?" I would say: If he had intended the transitive meaning, he would have used the preposition ‘ala.

How ugly is blind imitation (taqlid) and accepting claims without proof! How great is the deception of Satan against the imitators when he lures them into imitating their forefathers in the worship of statues, rubbing their foreheads in the dust for them, while they believe they are upon something [of truth], striving to support their school of thought, and arguing against the people of truth on behalf of their falsehood. It is sufficient shame for the people of imitation that the idolaters are among them.

"You": This is an emphatic pronoun, without which the sentence would be grammatically invalid, because conjunction to a pronoun that is effectively part of the verb is prohibited. Similar to this is: "Dwell, you and your wife, in Paradise." He intended that the imitators and the imitated are all strung together on the thread of misguidance, which is not hidden from anyone with the slightest bit of sense, because both parties rely on no evidence, but rather on followed whims and an obeyed Satan, as they find it inconceivable that what they are upon could be misguidance.

"They said, 'Have you come to us with the truth, or are you of the jesters?'"