Tafsir of As-Saffat 37:151-152

"Verily, it is out of their falsehood that they say," (151) An initiation from the side of the Exalted, not falling under the interrogation [of the previous verses], set forth to invalidate the very foundation of their corrupt doctrine by clarifying that its basis is nothing but explicit falsehood and hideous fabrication, devoid of any proof or semblance of evidence.

"And verily, they are liars," (152) In what they profess as their religion, absolutely, or in this specific statement. In this, there is an emphasis on His saying: "out of their falsehood." It has been recited as "waladu Allah" (offspring of God) in the genitive construction, with walad being in the nominative case as the predicate of an omitted subject—that is, "They say: 'The angels are the offspring of God'." Walad (offspring) is a noun in the meaning of a passive participle, applicable to the masculine and feminine, and to the singular and plural; hence, it is used here as a predicate for the [implied] "angels."