His will as an excuse, for His will cannot serve as an excuse for anyone.
“Say, ‘Do you have any knowledge that you can produce for us?’” That is, a scripture or proof from Allah. “‘You follow nothing but conjecture, and you do nothing but lie.’” That is, in what you adhere to, you follow only conjecture, without knowledge or certainty, and you merely speak falsehood.
“Say, ‘Allah alone has the conclusive proof. Had He willed, He would have guided you all.’” (149) “Say, ‘Bring forward your witnesses who testify that Allah has forbidden this.’ If they testify, do not testify with them. And do not follow the desires of those who deny Our signs, those who do not believe in the Hereafter, and who equate others with their Lord. (150) Say, ‘Come, I will recite to you what your Lord has forbidden to you: that you associate nothing with Him; that you show kindness to your parents; that you do not kill your children out of poverty—We provide for you and for them; that you do not approach shameful deeds, whether outward or inward; and that you do not kill the soul which Allah has forbidden, except by right. This He has enjoined upon you, so that you may understand.’” (151)
“Say, ‘Allah alone has the conclusive proof’”: that is, the complete proof against His creation, through the Book, [the Messenger] (1), and clear exposition. “‘Had He willed, He would have guided you all’”: this indicates that He did not will faith for the disbeliever; had He willed it, He would have guided him.
“Say, ‘Bring forward’”: this expression is used when addressing one person, two people, or a group. “‘Your witnesses who testify’”: that is, bring your witnesses who testify. “‘That Allah has forbidden this’”: this refers to their previously mentioned prohibition of certain things for themselves and their claim that Allah had commanded them to do so. “‘If they testify’”: falsely. “‘Do not testify with them,’” you, and do not follow the desires of those who deny Our signs, who do not believe in the Hereafter, and who equate others with their Lord—that is, they associate partners with Him.
His saying, exalted is He: “Say, ‘Come, I will recite to you what your Lord has forbidden to you: that you associate nothing with Him.’” This was because they asked, saying: What is it that Allah, exalted is He, has forbidden? So He said, exalted is He: “Say, ‘Come, I will recite’”—that is, I will read to you what your Lord has truly and certainly forbidden to you, not conjecture or falsehood, as you claim.
If it is asked: What is meant by His words, “What your Lord has forbidden to you: that you associate nothing with Him,” when what is forbidden is associating partners with Him, not refraining from associating partners with Him?