The Messenger of Allah (SWT) once said: "When any one of you is fasting, he should refrain from all indecencies. He should not raise his voice. If anyone fights with him or abuses him, he should not retaliate, but simply say he is fasting." - Abu Hurayra

Fasting is not simply about not eating or drinking; it is a period where man must reject evil in every form. Fasting makes one sincere and his personality should be of seriousness. No amount of provocation should produce a reaction from him. He should not create a problem to society.

The Prophet Muhammed (SAW) also said: "A number of people get no return for their fast except hunger and thirst" - Buhkari

In the case of the person who fasts but doesn't leave acts of lying, arguing and other wrong practices, then Allah does not need him to abstain from food.