Musnad Ahmad 289:13

Ali ibn Ishaq narrated to us, he said: Abdullah—meaning Ibn al-Mubarak—informed us, he said: Abd al-Rahman ibn Yazid ibn Jabir informed us, from Sulayman ibn Musa, from Abu Razin al-Uqayli, who said: I came to the Messenger of Allah, peace and blessings of Allah be upon him, and said: "O Messenger of Allah, how does Allah bring the dead to life?" He said: "Have you not passed by a land of your land that was barren, then you passed by it and it was fertile?" He said: "Yes." He said: "Likewise is the Resurrection." He said: "O Messenger of Allah, and what is faith?" He said: "That you testify that there is no god but Allah alone, with no partner, and that Muhammad is His servant and His Messenger; and that Allah and His Messenger are more beloved to you than anything else; and that being burned in the fire is more beloved to you than associating partners with Allah; and that you love a person who has no kinship with you, not loving him except for the sake of Allah, the Mighty and Majestic. If you are like that, then the love of faith has entered your heart, just as the love of water enters the heart of the thirsty one on a scorching day." I said: "O Messenger of Allah, how can I know that I am a believer?" He said: "There is no servant of my nation—or this nation—who performs a good deed and knows that it is a good deed, and that Allah, the Mighty and Majestic, will reward him with good for it; and does not perform an evil deed and know that it is an evil deed, and seeks forgiveness from Allah, the Mighty and Majestic, for it, and knows that no one forgives except Him, but that he is a believer."