It is narrated from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "The best of this Ummah is my generation, then those who come after them, then those who come after them. Then there will come people whose oaths will precede their testimonies, and whose testimonies will precede their oaths."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 10299