Sayyiduna Abdullah (may Allah be pleased with him) narrates from the Prophet (peace and blessings be upon him) that he (peace and blessings be upon him) said: "The best people are those of my generation, then those who come after them, then those who come after them." The narrator says: I do not know whether he said it a third or a fourth time. "Then after them people will come whose testimony will precede their oath, and whose oath will precede their testimony."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشهادات / 20598