What is the ruling on the fast of a father who quarrels, shouts, and threatens to hit his children while he is fasting?

The father's fast is valid, but he should be reminded of the importance for the fasting person to control his tongue and safeguard it from abuse, based on the words of Allah Almighty: "And speak to people good words" and "And tell My servants to say that which is best." And in the Two Sahihs, the Prophet, peace and blessings be upon him, said: "If it is a day of fasting for any one of you, he should not utter obscene speech or raise his voice or act ignorantly. If someone insults him or fights him, he should say: 'Indeed, I am fasting.'"