Abdullah bin Abbas reported,

The Messenger of Allah ﷺ combined his prayers during a journey he made on the expedition of Tabuk. He combined the Zuhr and Asr prayers, and the Maghrib and Isha prayers.Saeed said, "I asked Ibn Abbas, 'What led him to do that?'"Ibn Abbas replied, "He wished not to place his community in hardship."

Azami 2882

Sahih

عن ابن عباس

أن رسول الله ﷺ الجمع بين الصلاة في سفرة سافرها في غزوة تبوك، فجمع بين الظهر والعصر، والمغرب والعشاء. قال سعيد: فقلت لابن عباس: ما حمله على ذلك؟ قال: أراد أن لا يحرج أمته.

الأعظمي 2882صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Prayer
Chapter
Witr prayer
Section
Combining two prayers while traveling ﷺ
Numbering
Jami al-Kamil 2882 (2nd edition)
Azami 2882