The Expiation for Intercourse for a Traveling Fasting Person

Question:
A questioner asks and says: If a person travels while fasting during his journey, and then has intercourse with his wife after arriving, does he owe an expiation? Or do we say that he breaks his fast through intercourse, and nothing is required of him except making up the fast?

Answer:
No, if he arrived at his home and abstaining from food and drink became obligatory for him for the rest of the day. And if he has intercourse while abstaining is obligatory for him, this is forbidden for him and the expiation becomes obligatory for him: fasting two consecutive months. Because he had intercourse while abstaining was obligatory for him. Abstaining means refraining from intercourse and refraining from eating and drinking. How can abstaining be obligatory for him and yet he has intercourse? This is not acceptable. Yes.