Zayd bin Yuthay' relates: We asked Sayyiduna Ali (may Allah be pleased with him): "With what were you sent?" He said: "With four things," and he mentioned them. Then he said: "A Muslim and a polytheist shall not come together in Hajj after this year, and whoever has no covenant is given four months."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجزية / 18744