Isma'il bin Ubayd bin Rifa'ah bin Rafi' (may Allah have mercy on him) narrates from his father Ubayd, from Sayyiduna Rifa'ah bin Rafi' (may Allah be pleased with him), that the Messenger of Allah (peace and blessings be upon him) said to Sayyiduna Umar bin al-Khattab (may Allah be pleased with him): "O Umar, gather your people for me." So he gathered them, and when they arrived at the door of the Messenger of Allah (peace and blessings be upon him), Sayyiduna Umar (may Allah be pleased with him) went in to him and said: I have gathered my people for you. The Ansar heard this and said: Revelation has come down concerning Quraysh. So those who wanted to listen and to see came, to find out what he (peace and blessings be upon him) would say to them. The Messenger of Allah (peace and blessings be upon him) came out, stood among them and said: "Is there anyone among you who is not from you?" They said: Yes, among us are our ally, the son of our sister and our freed slave. The Messenger of Allah (peace and blessings be upon him) said: "Our ally is from us, the son of our sister is from us, and our freed slave is from us. You are listening: indeed, my close ones on the Day of Resurrection are the God-fearing. If you are those, then well and good; otherwise, take care, lest people come with deeds on the Day of Resurrection while you come with burdens, and you are turned away from." Then he (peace and blessings be upon him) called out and said: "O people, Quraysh are a people of trust. Whoever seeks calamities or stumbles for them (Zuhayr said: and I think it was 'stumbles'), may Allah throw him down on his face." He (peace and blessings be upon him) said this three times.
Hadith Referenceالمعجم الكبير للطبراني / باب الراء / 4529