Tell Followers Not to Mix Socially with the Non-believer

[53.29] Therefore turn aside from him who turns his back upon Our reminder and does not desire anything but this world's life.

[58.14] Have you not seen those who befriend a people with whom Allah is wroth? They are neither of you nor of them, and they swear falsely while they know.
[58.15] Allah has prepared for them a severe punishment; surely what they do is evil...
[58.17] Neither their wealth nor their children shall avail them aught against Allah; they are the inmates of the fire, therein they shall abide...
[58.19] The Shaitan has gained the mastery over them, so he has made them forget the remembrance of Allah; they are the Shaitan's party; now surely the Shaitan's party are the losers.
[58.20] Surely (as for) those who are in opposition to Allah and His Apostle; they shall be among the most abased...
[58.22] You shall not find a people who believe in Allah and the latter day befriending those who act in opposition to Allah and His Apostle, even though they were their (own) fathers, or their sons, or their brothers, or their kinsfolk; these are they into whose hearts He has impressed faith, and whom He has strengthened with an inspiration from Him: and He will cause them to enter gardens beneath which rivers flow, abiding therein; Allah is well-pleased with them and they are well-pleased with Him these are Allah's party: now surely the party of Allah are the successful ones.

[60.1] O you who believe! do not take My enemy and your enemy for friends: would you offer them love while they deny what has come to  you of the truth, driving out the Apostle and yourselves because you believe in Allah, your Lord? If you go forth struggling hard in My path and seeking My pleasure, would you manifest love to them? And I know what you conceal and what you manifest; and whoever of you does this, he indeed has gone astray from the straight path.
[60.2] If they find you, they will be your enemies, and will stretch forth towards you their hands and their tongues with evil, and they ardently desire that you may disbelieve.
[60.3] Your relationship would not profit you, nor your children on the day of resurrection; He will decide between you; and Allah sees what you do.

[60.13] O you who believe! do not make friends with a people with whom Allah is wroth; indeed they despair of the hereafter as the unbelievers despair of those in tombs.