The Prophet (ﷺ) combined his prayers so that his community might not fall into hardship

Reference: Sunan Abi Dawud 1211

Sunan Abi Dawud 1211
Narrated Ibn 'Abbas:

The Messenger of Allah (ﷺ) combined the noon and afternoon prayers, and the sunset and night prayers at Medina without any danger and rain. He was asked: What did he intend by it ? He replied: He intended that his community might not fall into hardship.

دَّثَنَا يَحْيَى بْنُ يَحْيَى، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنْ أَبِي الزُّبَيْرِ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ صَلَّى رَسُولُ اللَّهِ صلى الله عليه وسلم الظُّهْرَ وَالْعَصْرَ جَمِيعًا وَالْمَغْرِبَ وَالْعِشَاءَ جَمِيعًا فِي غَيْرِ خَوْفٍ وَلاَ سَفَرٍ ‏.
Reference  : Sunan Abi Dawud 1211
In-book reference  : Book 4, Hadith 14
 
The Prophet (ﷺ) combined his prayers without being in a state of fear or on a journey

Reference: Sahih Muslim 705a

Sahih Muslim 705a
Ibn 'Abbas reported:

The Messenger of Allah (ﷺ) observed the noon and afternoon prayers together, and the sunset and Isha' prayers together without being in a state of fear or in a state of journey.

دَّثَنَا يَحْيَى بْنُ يَحْيَى، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنْ أَبِي الزُّبَيْرِ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ صَلَّى رَسُولُ اللَّهِ صلى الله عليه وسلم الظُّهْرَ وَالْعَصْرَ جَمِيعًا وَالْمَغْرِبَ وَالْعِشَاءَ جَمِيعًا فِي غَيْرِ خَوْفٍ وَلاَ سَفَرٍ ‏.
Reference  : Sahih Muslim 705a
In-book reference  : Book 6, Hadith 59
Additional References:
 
Combining prayers is the Sunnah of the Prophet (ﷺ)

Reference: Sahih Muslim 705h

Sahih Muslim 705h
'Abdullah b. Shaqiq al-'Uqaili reported:

A person said to Ibn 'Abbas (as he delayed the prayer): Prayer. He kept silence. He again said: Prayer. He again kept silence, and he again cried: Prayer. He again kept silence and said: May you be deprived of your mother, do you teach us about prayer? We used to combine two prayers during the life of the Messenger of Allah (ﷺ).

وَحَدَّثَنَا ابْنُ أَبِي عُمَرَ، حَدَّثَنَا وَكِيعٌ، حَدَّثَنَا عِمْرَانُ بْنُ حُدَيْرٍ، عَنْ عَبْدِ اللَّهِ بْنِ شَقِيقٍ الْعُقَيْلِيِّ، قَالَ قَالَ رَجُلٌ لاِبْنِ عَبَّاسٍ الصَّلاَةَ فَسَكَتَ ‏.‏ ثُمَّ قَالَ الصَّلاَةَ ‏.‏ فَسَكَتَ ثُمَّ قَالَ الصَّلاَةَ فَسَكَتَ ‏.‏ ثُمَّ قَالَ لاَ أُمَّ لَكَ أَتُعَلِّمُنَا بِالصَّلاَةِ وَكُنَّا نَجْمَعُ بَيْنَ الصَّلاَتَيْنِ عَلَى عَهْدِ رَسُولِ اللَّهِ صلى الله عليه وسلم ‏.‏
Reference  : Sahih Muslim 705h
In-book reference  : Book 6, Hadith 68
 
Rasulullah (ﷺ) would delay and hasten prayers in order to combine them"

Reference: Sahih Muslim 705e

Sahih Muslim 705e
Ibn 'Abbas reported:

I observed with the Messenger of Allah (ﷺ) eight (rak'ahs) in combination, and seven rak'ahs in combination. I (one of the narrators) said: O Abd Sha'tha', I think that he (the Holy Prophet) had delayed the noon prayer and hastened the afternoon prayer, and he delayed the sunset prayer and hastened the 'Isha' prayer. He said: I also think so.

وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا سُفْيَانُ بْنُ عُيَيْنَةَ، عَنْ عَمْرٍو، عَنْ جَابِرِ بْنِ زَيْدٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ صَلَّيْتُ مَعَ النَّبِيِّ صلى الله عليه وسلم ثَمَانِيًا جَمِيعًا وَسَبْعًا جَمِيعًا ‏.‏ قُلْتُ يَا أَبَا الشَّعْثَاءِ أَظُنُّهُ أَخَّرَ الظُّهْرَ وَعَجَّلَ الْعَصْرَ وَأَخَّرَ الْمَغْرِبَ وَعَجَّلَ الْعِشَاءَ ‏.‏ قَالَ وَأَنَا أَظُنُّ ذَاكَ ‏.‏
Reference  : Sahih Muslim 705e
In-book reference  : Book 6, Hadith 65