The time of Isha begins when the twilight disappears

It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that "al-shafaq" means the redness. Abu Mus'ab says that according to Malik (may Allah have mercy on him), "al-shafaq" means the redness.

Sayyiduna Ibn Umar (may Allah be pleased with them both) says: Shafaq means the redness.

Sayyiduna Ibn Umar (may Allah be pleased with them both) narrates it as mawquf (as his own statement).
It has also been narrated from Atiq bin Ya'qub, from Malik, from Nafi', as marfu' (attributed to the Prophet), but the correct view is that it is mawquf.

It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "'Al-shafaq' (twilight) means the redness; when the redness disappears, the prayer becomes obligatory."

It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that "shafaq" means the redness. Sayyiduna Umar (may Allah be pleased with him), Ali (may Allah be pleased with him) and Abu Hurayrah (may Allah be pleased with him) say that "shafaq" means the redness.

(a) Sayyiduna Ubadah bin al-Samit and Shaddad bin Aws (may Allah be pleased with them both) say that shafaq is of two kinds: the redness and the whiteness; when the redness disappears, the prayer becomes permissible. And fajr (dawn) is of two kinds: the one that spreads lengthwise and the one that spreads widthwise; when the one that spreads widthwise breaks forth, the prayer becomes permissible.
(b) Makhul (may Allah have mercy on him) says that when the redness has gone, the prayer should be prayed. And Sufyan (may Allah have mercy on him) says that in our view it is more appropriate (more beloved) that we offer the prayer when the redness has gone, because the whiteness does not go until the night ends.
(c) Sayyiduna Jabir (may Allah be pleased with him) reports the times of prayer from the Prophet (peace and blessings be upon him), that he (peace and blessings be upon him) offered the Isha prayer before the redness had disappeared. This narration contradicts the other narrations.

It is narrated from Abdullah bin al-Harith al-Makhzumi that in the first (narration) he said that the time of Isha is when the redness disappears, and in the second he said that Abdullah bin al-Harith said: Then he said concerning Isha: "I think up to a third of the night."

It is narrated from Sayyiduna Nu'man bin Bashir (may Allah be pleased with him) that (he said): I know the time of this prayer (Isha) better than anyone. The Messenger of Allah (peace and blessings be upon him) used to pray it at the time the moon set on the third night.