وجعلنا على قلوبهم أكنة أن يفقهوه وفي آذانهم وقرا وإذا ذكرت ربك (17:46) بالانجليزي

(17:46) and we cover their hearts with a covering so that they understand nothing and we make their ears hard of hearing. *51 And when in the Qur'an you mention your one Lord only, they turn their faces away in aversion. *52

Tafseer Abu-al-A'la Maududi

Page 286 English Traditional

*51) This refers to the Divine law according to which those people, who do not believe in the Hereafter, cannot benefit from the Qur'an. Allah has attributed this law to Himself, as if to say, "The natural result of disbelief in the Hereafter is that the heart of such a man becomes dull and his ears become deaf to the Message of the Qur'an, for Qur'an bases its invitation on the belief in the Hereafter. So it warns the people that they should not be deluded by this apparent aspect of the worldly life if there appears to be none to call them to account here; for it does not mean they are not at all accountable and answerable to anyone. Likewise if Allah allows freedom of belief to practise shirk, atheism, disbelief or Tauhid with impunity in this world, and their practice dces not appear to make any practical difference in this world, it dces not mean that these things do not produce any results at alI. For, in fact, everyone shall be accountable and answerable but after death in the Next World. Then every one will realize that the doctrine of Tauhid alone is true and all other doctrines are false. For, if at present the consequences of deeds do not appear after death they shall inevitably appear, but now the Reality has been hidden behind an invisible curtain. There is an inevitable moral law according to which submission to it will bear its fruit and disobedience shall incur its losses. As decisions according to this moral law will be made in the Hereafter, you should not be enticed by the charms of this transitory life. You should, therefore, keep in view that ultimately you shall have to render an account of all your deeds in this world before your Lord, and adopt that true creed and moral attitude which may be conducive to your success in the Hereafter" .
From this it must have become obvious that if a man does not believe in the Hereafter, he will never consider the message of the Qur'an worth his while but will hanker after this world and its joys which he can feel and experience. Naturally his ears will not listen to the Message and it will never reach the depths of his heart. AIIah has stated this psychological fact in this verse.
In this connection, it should be remembered that the words contained in this verse were uttered by the disbelievers of Makkah as quoted in verse 5 of Surah 41: "They say, O Muhammad, a covering has fallen over our hearts, and our ears are deaf for the Message you give and there is a curtain between you and us. You may go on with your work and we will do whatever we desire." Here the same words have beer cited, as if to say, "You consider this state of yours to be a virtue, whereas this is a curse which has fallen on you according to the Divine Law because of your disbelief of the Hereafter. "
*52) That is, "They do not like it at all that you should consider Allah alone as your Lord and not mention the Lords they have set up. " They seem to think it strange that one should go on praising Allah and never mention the "miracles" of their elders and saints nor praise them for their favours. For, according to them, Allah has delegated the powers of His Godhead to their great ones. Therefore, they say, "What a strange fellow he is! He believes that the knowledge of the unknown, and all the power and authority belong to One Allah alone. Why does he not pay tribute to those who give us children, cure us of diseases, and help make our commerce flourish, in short, fulfil all our wishes and desires?"