What do “asr-ı evvel” and “asr-ı sani” mean?

“Asr-ı evvel” refers to the first time period for the Asr (afternoon) prayer, while “asr-ı sânî” refers to the second time period for the Asr prayer. The time for the Asr prayer begins when the time for the Dhuhr (noon) prayer ends. Since there is a difference of opinion among jurists regarding the evidence they use to determine when the Dhuhr prayer time ends, there is also a difference regarding when the Asr prayer time begins. According to Imam Abu Yusuf, Imam Muhammad, and the other three madhhab imams, when the shadow of an object (excluding the shadow present at the zenith, known as fey-i zevâl) becomes equal to the length of the object itself as the sun declines from its highest point, the time for Dhuhr ends and the time for Asr begins. (Merghinani, al-Hidaya, 1/40; Shirbini, Mughni’l-muhtaj, 1/299-300; Desuqi, Hashiya, 1/177; Ibn Qudama, al-Mughni, 1/271-272) This time is called “asr-ı evvel” (the first time for the Asr prayer).

According to Imam Abu Hanifa, however, the time for Dhuhr ends when the shadow of an object (excluding fey-i zevâl) becomes twice the length of the object itself. This time is called “asr-ı sânî” (the second time for the Asr prayer). (Kasani, Bada’i, 1/122; Merghinani, al-Hidaya, 1/40; Zayla’i, Tabyin, 1/79)

The Presidency of Religious Affairs (Diyanet İşleri Başkanlığı) arranges the time for the Asr prayer in its published Diyanet Calendar according to the “asr-ı evvel” opinion, and prayers are performed based on the asr-ı evvel ijtihad.

Source: T.C. Diyanet İşleri Başkanlığı, Din İşleri Yüksek Kurulu