Is it better to advance or delay when combining two prayers?

Q: Regarding combining and shortening the prayers between Dhuhr and Asr, what is better: praying immediately after the Dhuhr adhan, or delaying it until the middle of the two times?

A: If the traveler intends to depart from his location before the sun reaches its zenith, it is prescribed for him to pray Dhuhr and Asr as a delayed combination. However, if he departs after the sun has passed its zenith, it is better for him to pray Dhuhr and Asr as an advanced combination. The ruling is the same for Maghrib and Isha: if he departs before sunset, he delays Maghrib and combines it with Isha as a delayed combination; if he departs after sunset, he advances Isha and combines it with Maghrib as an advanced combination. This is the Sunnah of the Prophet (peace and blessings be upon him) in what we have mentioned.
As for the resident, he has the choice: if he wishes, he may combine as a delayed combination, and if he wishes, he may combine as an advanced combination. The best for him is to pray each prayer in its proper time, as the Prophet (peace and blessings be upon him) did in Mina during the Farewell Pilgrimage, for he was a resident and used to pray each prayer in its time. If there is a need for combining, there is no blame on him, for the Prophet (peace and blessings be upon him) combined prayers during the expedition to Tabuk while he was a resident. Likewise, the sick person does whatever is most comfortable for him regarding combining—meaning either an advanced or a delayed combination. If he does not have a hardship that necessitates combining, he should pray each prayer in its time; this is the best for him. And if he combines, there is nothing wrong with it.