Anas said (explaining the meaning) of the following Quranic verse "They used to sleep but little of the night" (51: 17): They (the people) used to pray between the Maghrib and 'Isha. The version of Yahya adds: The verse tatajafa junubuhum also means so.
Explanation & Benefits
Shaykh Umar Farooq Saeedi
1322. Commentary: Benefit: In the aforementioned verses, there is encouragement for standing in prayer at night (qiyam al-layl), and an extension of its time. If a person performs voluntary prayers (nawafil) between Maghrib and Isha, as has been reported from the Companions (radi Allahu anhum), then this too is included in qiyam al-layl. However, preference and superiority are given to the last part of the night.
Source: Sunan Abu Dawood – Commentary by Shaykh Umar Farooq Saeedi, Page: 1322