And We will turn away their hearts and their eyes just as they refused to believe in it [i.e., the revelation] the first time. And We will leave them in their transgression, wandering blindly.
Asking for Miracles and Swearing to Believe if They Come
Allah states that the idolators swore their strongest oaths by Allah,
لَئِن جَآءَتْهُمْ ءَايَةٌ
(that if there came to them a sign...) a miracle or phenomenon,
لَّيُؤْمِنُنَّ بِهَا
(they would surely believe therein.) affirming its truth,
قُلْ إِنَّمَا الاٌّيَـتُ عِندَ اللَّهِ
(Say: "Signs are but with Allah.") 6:109 meaning: Say, O Muhammad - to those who ask you for signs out of defiance, disbelief and rebellion, not out of the desire for guidance and knowledge - "The matter of sending signs is for Allah. If He wills, He sends them to you, and if He wills, He ignores your request." Allah said next,
The previous verses had mentioned how obstinate people failed to benefit from clear signs of Allah and open miracles of His Messenger and kept on denying the message of truth. The present verses mention how they took a new turn, and demanded particular miracles from the Holy Prophet ﷺ . As reported by Ibn Jarir, the Quraysh chiefs asked that they be shown the miracle of turning the Mount of Safa into solid gold; if so, they would accept that he was a prophet and messenger, and that they would embrace Islam. The Holy Prophet ﷺ said: All right, make a solid agreement that, if this miracle is shown, all of you will become Muslims. They took solemn oaths. The Holy Prophet ﷺ stood up to pray that Allah turns the Mount into gold. Sayyidna Jibra'il (علیہا السلام) came with Wahy which said: If you wish, We shall make this whole Mount a Mount of gold, but the consequence will be that, according to the customary Divine Law, all of them - if they still fail to believe - shall be destroyed through a mass punishment, as has been happening with past communities who demanded a miracle which was shown, yet they reverted back to denial when the wrath and punishment of Allah overtook them. Since the Holy Prophet ﷺ was aware of their habitual obstinacy, and because he was in mercy the foremost, he said that he was not going to pray for that miracle anymore. Thereupon, the following verse was revealed: وَأَقْسَمُوا بِاللَّـهِ جَهْدَ أَيْمَانِهِمْ (And they swore by Allah on eloquent oaths - 109). Reported here is the sworn saying of the disbelievers that they would embrace Islam if they can see the miracle demanded by them. After that, in the sentence which follows immediately, it was said: إِنَّمَا الْآيَاتُ عِندَ اللَّـهِ (Signs are, definitely, with Allah - 109). This contains an answer to their saying. It has been declared here that all signs and miracles are within the power and control of Allah Ta` a1a. As for the miracles already manifested, they too were from Him - and those being demanded now, they too lie within His absolute control. But, according to the dictate of reason and justice, they had no right to make such a demand - because, the Holy Prophet ﷺ claims to be a Messenger of Allah, in support of which, he has already presented proofs and evidences in the form of miracles. Now, the other party does have the right to question these proofs and evidences by showing the proofs of their being false. But, the attitude of not cross-examining evidences presented and yet demanding some other evidences would be like the scenario in a law court where the respondent would avoid cross-examining the witness presented by the plaintiff and take the plea that he does not accept the evidence of these witnesses and that he would accept what is said particularly by such and such a person in his statement. Obviously, no court would consider this plea worth hearing.
The truth may be laid before a man with all its supporting arguments and he will still reject it. There is just one reason for this, i.e. his looking at things perversely instead of looking at them in a straightforward manner. An argument may be most rational and based on sound reasoning, but if one is not inclined to accept it, he will find some words or the other to reject it. For example, instead of viewing the arguments of a preacher as definitive, he will start discussing whether all the previous great men were all wrong and strangers to the Truth, and will go on to raise other similar points. It is extremely difficult for one who has developed such a temperament to arrive at the right path. He can give the wrong colour to any subject and seek an excuse to reject it. In order to contradict theoretical arguments, he will find the excuse that they were against the creed of his ancestors. Similarly, in order to allege the falsity of physical observations, he will voice the opinion that they are optical illusions or mere conjuring tricks. This attitude, which impedes the acceptance of theoretical arguments, will likewise obstruct the acceptance of physical facts in support of the truth. One who is determined to remain unreceptive to the truth will, as always, have to go without guidance. Such deniers are arrogant in nature. They want to see themselves set above others at any cost. When a preacher appears before them with a message of Truth, it frequently happens that he is a stranger in those surroundings and has none of the elegant trappings of the times. So, forming any connection with him amounts to degrading one’s position. Those with a superiority complex are therefore unable to accept him. Offering a variety of excuses, they reject him.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.