Ibn Abi Najih narrated from his father that he said: Sayyiduna Ibn Umar (may Allah be pleased with them both) was asked about fasting on the Day of Arafah, so he replied: I performed Hajj with the Prophet (peace and blessings be upon him) and he did not fast on the Day of Arafah, and I performed Hajj with Sayyiduna Abu Bakr (may Allah be pleased with him) and he also did not fast, and then I performed Hajj with Sayyiduna Umar (may Allah be pleased with him) and he also did not fast on that day, then I performed Hajj with Sayyiduna Uthman (may Allah be pleased with him) and he also did not fast on that day, and I also do not fast on that day, nor do I order fasting nor do I forbid it.
From these ahadith, it is established that it is not permissible for the pilgrim (haji) to fast on the Day of Arafah and during the Days of Tashreeq. For this reason, the scholars have declared fasting for pilgrims during these days to be disliked (makruh). However, the pilgrim who has performed Hajj al-Tamattu‘ and does not have the means to offer a sacrifice, may fast during the Days of Tashreeq, as is the position of Imam Malik, Shafi‘i, Ahmad, and Ishaq rahimahumullah.