I saw the Messenger of Allah (ﷺ) combining the sunset and Isha' prayers when he was in a hurry on a journey.
Sahih Muslim Book 6, Hadith 54
← Previous Hadith Nafi' reported that when Ibn 'Umar was in a state of hurry on a journey, he combined the sunset and 'Isha' prayers after the twilight had disappeared, and he would say that when the Messenger of Allah (ﷺ) was in a state of hurry on a journey, he combined the sunset and 'Isha' prayers.

Sahih Muslim Book 6, Hadith 53 Next Hadith → I saw the Messenger of Allah (ﷺ) delaying the sunset prayer till he would combine it with the 'Isha' when he hastened to set out on a journey.

Sahih Muslim Book 6, Hadith 55