Musannaf Ibn Abi Shayba 33:208

Abdullah ibn Idris narrated to us, from Isma'il ibn Abi Khalid, from Zayd, who said: When death approached Abu Bakr, he sent for Umar and said: "I am advising you with a testament; if you preserve it, [know that] Allah has a right in the night which He does not accept in the day, and Allah has a right in the day which He does not accept in the night. And He does not accept a supererogatory act until the obligatory act is performed. The scales of those whose scales are light on the Day of Resurrection are only light because of their following falsehood in the world and its heaviness upon them; and it is fitting for a scale in which nothing is placed but falsehood that it should be light. The scales of those whose scales are heavy on the Day of Resurrection are only heavy because of their following the truth in the world and its heaviness upon them; and it is fitting for a scale in which nothing is placed on the Day of Resurrection but the truth that it should be heavy. Do you not see that Allah mentioned the people of Paradise by the good they did and overlooked their evil deeds, so the speaker says: 'Would that I reached them'? And He mentioned the people of the Fire by the evil they did and rejected their good deeds, so the speaker says: 'I am better than them'? He mentioned the verse of mercy and the verse of punishment, so the believer is hopeful and fearful, and he does not wish upon Allah anything but the truth, and he does not cast himself into destruction. If you preserve this saying of mine, then let no absent thing be more beloved to you than death, and you must inevitably face it. But if you neglect this saying of mine, then let no absent thing be more hateful to you than it, and you will not be able to escape Him."