Ali 'Imran 3:118

Ya ayyuha allatheena amanoola tattakhithoo bitanatan min doonikum laya/loonakum khabalan waddoo ma AAanittum qad badatialbaghdao min afwahihim wama tukhfee sudooruhumakbaru qad bayyanna lakumu al-ayati inkuntum taAAqiloon

O you who have believed, do not take as intimates those other than yourselves [i.e., believers], for they will not spare you [any] ruin. They wish you would have hardship. Hatred has already appeared from their mouths, and what their breasts conceal is greater. We have certainly made clear to you the signs, if you will use reason.

O you who believe, do not take anyone as an insider but those from among your own selves. They would spare no effort to do you mischief. They want you to be in trouble. Malice has come out of their mouths while what is concealed in their hearts is still worse. We have made the signs clear to you, if only you understand.