We were traveling and we prayed Maghrib, and a person joined us to pray 'Isha'. When he had prayed two rak'ahs and we stood up for the third, he sat down, completed the tashahhud, and said the taslim, and did not stand up with us.
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The questioner : And this says: We were traveling and we prayed Maghrib, and a person joined us to pray 'Isha'. When he had prayed two rak'ahs and we stood up for the third, he sat down, completed the tashahhud, and said the taslim, and did not stand up with us. He then came and prayed a fourth rak'ah because he is a traveler. Is his action valid?
The Shaykh : It is valid. That is, if he was a traveler and joined with the intention of praying 'Isha' with a group praying Maghrib, and when they sat for the first tashahhud, he completed the first tashahhud and said the taslim, there is no harm, as long as he had intended to shorten the prayer. However, if he completed the prayer with the imam and then came and prayed the fourth rak'ah after his taslim, that is better.
The Shaykh : It is valid. That is, if he was a traveler and joined with the intention of praying 'Isha' with a group praying Maghrib, and when they sat for the first tashahhud, he completed the first tashahhud and said the taslim, there is no harm, as long as he had intended to shorten the prayer. However, if he completed the prayer with the imam and then came and prayed the fourth rak'ah after his taslim, that is better.