(a) Jabir bin Zayd (may Allah have mercy on him) said: I heard Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) say: I prayed with the Prophet (peace and blessings be upon him) eight (rak'ahs) together and seven (rak'ahs) together.
(b) Sa'id bin Jubayr (may Allah have mercy on him) narrates from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both): I said to Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both): Why did he (peace and blessings be upon him) do that? He said: So that there would be no hardship for his (peace and blessings be upon him) Ummah. Sufyan (may Allah have mercy on him) added some words: without fear or journey.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5547