Wa `alaykum as-salamu wa rahmatullahi wa barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
Dear questioner, we would like to thank you for the great confidence you place in us.
Fasting in Ramadan is the fourth pillar of Islam. Every able-bodied adult Muslim must fast during the month of Ramadan. Only travelers and sick people can break their fast and they must make up for it later.
Answering your question, Sheikh Muhammad Saleh Al-Munajjid, a well-known Saudi lecturer and author, said,
Fasting Ramadan is one of the pillars of Islam, and it is not permissible for an adult Muslim of sound mind who is accountable to break the fast in Ramadan except with an excuse, such as travelling, sickness and the like.
Whoever breaks the fast – even for one day – with no excuse has committed a major sin and has exposed himself to the wrath and punishment of Allah. He must repent sincerely and make up the days that he did not fast, according to the majority of scholars.
As for the one who deliberately does not fast in Ramadan, thinking it is permissible to do so, he has become a disbeliever. He should be asked to repent, and if he repents, all well and good, otherwise he is to be executed.
Whoever openly breaks the fast should be given a disciplinary punishment by the ruler, a punishment that will deter him and others like him from doing this grave act.
Imam Ibn Taymiyyah said:
“If a person breaks the fast in Ramadan, believing that to be permissible although he is aware of the prohibition on doing so, but he thinks that it is permissible for him, he must be executed. If he is an evildoer, he should be punished for breaking the fast of Ramadan, as the ruler sees fit. If he is ignorant, he is to be taught the ruling.” (Al-Fatawa al-Kubra, 2/473)
Ibn Hajar al-Haytami said:
“Major sins no. 140 and 141 are not fasting one of the days of Ramadan and breaking the fast by having intercourse or otherwise, with no excuse such as sickness or travelling.” (Az-Zawajir, 1/323)
The scholars of the Standing Committee for Issuing Fatwas said:
“Breaking the fast during the day in Ramadan on the part of one who is accountable is a major sin, if it is done without a legitimate excuse.” (Fatawa al-Lajnah ad-Da’imah, 10/357)
Ibn Baz said:
“Whoever breaks the fast on any day in Ramadan, with no legitimate excuse, has committed a grave evil. Whoever repents, Allah will accept his repentance, so he must repent to Allah sincerely, by regretting what he has done in the past and resolving not to repeat it, and he should ask his Lord for forgiveness a great deal, and hasten to make up the day that he did not fast.”
Ibn ‘Uthaymeen was asked about the ruling on breaking the fast during the day in Ramadan with no excuse. He replied:
“Breaking the fast during the day in Ramadan with no excuse is a major sin, and the individual becomes an evildoer thereby. He must repent to Allah and make up the day that he did not fast.” (Majmu` Fatawa wa Rasa’il al-`Uthaymeen, 9/89)
Allah the Almighty knows best.