One of his supplications
Nahj al-Balāgha|Volume 1|Book 1|Chapter 78
اللَّهُمَّ اغْفِرْ لِي مَا تَقَرَّبْتُ بِهِ إِلَيْكَ بِلِسَانِي ثُمَّ خَالَفَهُ قَلْبِي.
My Allah forgive me that with what I sought nearness to Thee with my tongue but my heart opposed and did not perform it.