Fasting the month of Ramadan and exerting efforts in doing so entails a generous reward. Abu Hurayrah (may Allah be pleased with him) reported that the Prophet (peace and blessings be upon him) said: “Whoever fasts the month of Ramadan with faith and seeks Allah’s pleasure and reward will have his previous sins forgiven.” (Reported by Ahmad)
In addition, breaking the fast of Ramadan without a valid excuse is an abominable and sinful act. The Prophet (peace and blessings be upon him) is reported to have said, “Whoever breaks the fast of Ramadan without having a legitimate excuse or being ill, he cannot make up for that day, even if he were to undertake a perpetual fast” (Reported by Al-Bukhari).
Sheikh Muhammad Iqbal Nadvi, director and imam of Al-Falah Islamic Centre, Oakville, Ontario, Canada, states the following: Islam permits breaking fasting for one who is not able to fast for genuine reasons of sickness and weakness, but I don’t think that is a good reason to say “my job is hard, so I can abandon the fast.”
In the case of someone who misses the fast due to weakness in the body that does not allow him to fast, a ransom is to be paid in compensation for the days he misses. But confirmation that someone qualifies for this category is needed, without which the law cannot be followed. This can be simply done by comparing two people at the same level of health and physical capability and both doing the same job. If one says he can fast and the other said he cannot, then it will not be a valid excuse.