مَنْ لَمْ يَدَعْ قَوْلَ الزُّورِ وَالْعَمَلَ بِهِ، فَلَيْسَ لِلَّهِ حَاجَةٌ فِي أَنْ يَدَعَ طَعَامَهُ وَشَرَابَهُ
Translation: Whoever does not give up false speech and acting upon it, Allah has no need of that person leaving food and drink.
Source: البخاري
لَمْ يَدَعْ means “did not give up.” قَوْلَ الزُّورِ denotes false or corrupt speech, and الْعَمَلَ بِهِ points to acting upon it. In فَلَيْسَ لِلَّهِ حَاجَةٌ, لَيْسَ is a defective verb of negation; Allah has no need of anyone’s abstention from food or drink.
Fasting involves more than hunger and thirst: reform of speech and conduct is part of its purpose. The report sharply warns a person who refrains from food while continuing falsehood and wrongful actions. It does not by itself settle every legal question about a fast’s technical validity.