It is narrated from Sayyiduna Ka'b bin Ujrah (may Allah be pleased with him); he said: The Messenger of Allah (peace and blessings be upon him) came out to us while we were sitting on a leather cushion, and he (peace and blessings be upon him) said: "After me there will be rulers. Whoever goes in to them, affirms their lies and helps them in their injustice is not from me and I am not from him, and he will not come to (my) Pond. And whoever does not affirm their lies and does not help them in their injustice is from me and I am from him, and he will come to the Pond."
Hadith Referenceالمعجم الكبير للطبراني / باب الكاف / 16344