Source: Jami at-Tirmidhi 3540
“Allah, Blessed is He and Most High, said: ‘O son of Adam! Verily as long as you called upon Me and hoped in Me, I forgave you, despite whatever may have occurred from you, and I did not mind. O son of Adam! Were your sins to reach the clouds of the sky, then you sought forgiveness from Me, I would forgive you, and I would not mind. So son of Adam! If you came to me with sins nearly as great as the earth, and then you met Me not associating anything with Me, I would come to you with forgiveness nearly as great as it.’”