Was Abdullah ibn Ubayy ibn Salul Jewish?

Abdullah ibn Ubayy ibn Salul was not Jewish. Rather, he was one of the chieftains of the Banu Khazraj, an Ansari Arab tribe, and had been prepared for leadership over the Aws and Khazraj before the arrival of the Prophet, peace and blessings be upon him. He was the head of the hypocrites, and he persisted in his hypocrisy and malice until he died. It was concerning him that the verses were revealed: "Ask forgiveness for them or do not ask forgiveness for them. If you ask forgiveness for them seventy times, Allah will not forgive them" and "And never offer a prayer for anyone of them who dies, nor stand by his grave. Indeed, they disbelieved in Allah and His Messenger and died while they were defiantly disobedient."