Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) says: It was said: O Messenger of Allah (peace and blessings be upon him), what is meant by "a way to Hajj" (al-sabil ila al-hajj)? He (peace and blessings be upon him) said: "What is meant by 'the way' (al-sabil) is provision for the journey and a mount."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 8623
Hasan al-Basri (may Allah have mercy on him) says: The Messenger of Allah (peace and blessings be upon him) was asked about the "way" (al-sabil), and he (peace and blessings be upon him) said: "Provision for the journey and a mount."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 8624