وَيَوۡمَ يَعَضُّ الظَّالِمُ عَلٰى يَدَيۡهِ يَقُوۡلُ يٰلَيۡتَنِى اتَّخَذۡتُ مَعَ الرَّسُوۡلِ سَبِيۡلًا‏. يٰوَيۡلَتٰى لَيۡتَنِىۡ لَمۡ اَتَّخِذۡ فُلَانًا خَلِيۡلًا‏. لَقَدۡ اَضَلَّنِىۡ عَنِ الذِّكۡرِ بَعۡدَ اِذۡ جَآءَنِىۡ​ ؕ وَكَانَ الشَّيۡطٰنُ لِلۡاِنۡسَانِ خَذُوۡلًا‏.

“And the day when the wrong-doer will bite his hands, saying: If only I had stood by the Messenger! Woe is me! If only I had not taken such a one for a friend! He led me astray from the Admonition that had come to me. Satan proved to be a great betrayer of man.”
(Surah Furqah, verses: 27-29)

This is a lecture that I delivered on the influence of companionship. Listen here

Download a PDF version of this talk here