Sayyiduna Salamah bin al-Akwa' (may Allah be pleased with him) narrates: The Messenger of Allah (peace and blessings be upon him) was in a red tent when a man came riding a pregnant mare followed by her foal. He asked: Who are you? He (peace and blessings be upon him) said: "I am the Messenger of Allah." He asked: When will the Hour come? He (peace and blessings be upon him) said: "That is of the unseen, and none knows the unseen except Allah." He asked: When will we get rain? He (peace and blessings be upon him) said: "That is of the unseen, and none knows the unseen except Allah." He asked: What is in my mare's belly? He (peace and blessings be upon him) said: "That is of the unseen, and none knows the unseen except Allah." He said: Give me your sword? He (peace and blessings be upon him) said: "Here, take it." So he took it, drew it from its sheath and shook it. The Messenger of Allah (peace and blessings be upon him) said: "You will never be able to do what you intended." Then he said: "This man came and thought: I will go to him and question him, then take my sword and kill him." So he put the sword back in its sheath.
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 6218