Is it a sin for a man to be absent from his wife for a long period out of necessity?

Question:
What is the ruling on the practice established by al-Faruq (the Second Caliph) that a man should not be absent from his wife for more than four months? Does a man who is compelled to do so commit a sin? Please inform us of specific conditions so that we may adhere to them?

Answer:
He used to write to those behind him for six months, returning in four or six months, if that was feasible. In any case, a person's circumstances vary, so a person must consider the benefit and the danger. If his absence from his wife for six months might lead to danger, he should not stay away for six months. However, if he takes her with him, the period might be shorter, two months, three months, or less. Consider the benefit. Time varies, and countries vary. This was an exercise of independent legal reasoning (ijtihad) by 'Umar regarding his conditions for his governors and soldiers. So the believer looks at the benefit and looks at the harm. If his absence from his wife involves danger, even if it is only one day, he should arrange his affairs and organize them so that no danger occurs. And if there is no danger, such as when she is with her family in a safe place, and he is compelled to stay away for more than six months, there is no harm if he is compelled to do so. As for a specific limit, there is no specific limit. Rather, the believer should beware of the causes of danger by taking her with him, or not delaying too long if he travels, or placing her in a safe place with her family, or with trustworthy women who will look after her until he returns, if there is a need to travel without her.