Al Kahf, 23 Ayah
18:23
وَلَا تَقُولَنَّ لِشَاْيۡءٍ إِنِّي فَاعِلٞ ذَٰلِكَ غَدًا ٢٣
Wa Lā Taqūlanna Lishay'in 'Innī Fā`ilun Dhālika Ghadāan
And never say of anything, "Indeed, I will do that tomorrow,"