Muhammad ibn Ali ibn Mahbub, from Ali ibn al-Sindi, from Hammad ibn Isa, from Hariz, from Muhammad ibn Muslim, who said: I asked Imam عليه السلام about the traveller who arrives in a land. Imam عليه السلام said: “If he considers within himself to stay for ten days, then let him complete (the prayer); but if he says, 'Today I will leave,' or 'Tomorrow I will leave,' and he does not know, then let him shorten (his prayer) until a month passes. If a month passes, then let him complete (the prayer). And he should not complete (the prayer) in less than ten (days), except in Mecca and Medina. And if he stays in Mecca and Medina for five (days), then let him complete (the prayer in full).”