When he was on his deathbed, Abu Bakr radiallahu anhu summoned for Umar radiallahu anhu to come to him. When the latter arrived, Abu Bakr radiallahu anhu said, "Verily, I want to give you some final advice - if you will accept it from me: Indeed, Allah ‘azza wa-jall has rights during the night, which He does not accept during the day; and rights during the day which He does not accept during the night. And verily, He ‘azza wa-jall does not accept voluntary acts of worship until the obligatory ones are first performed. Do you not see that those whose scales are heavy in the hereafter are heavy only because they followed the truth in the world, for doing so was heavy upon them (it required striving and effort, like an upward climb). And it is befitting for a scale to be heavy when only truth is placed on it. Do not see that those whose scales (scales of good deeds) are light in the hereafter are light only because they followed falsehood in the world; and doing so was light for them (easy, without strain, like descending a downward slope). And it is only befitting for a scale to be light when only falsehood is placed on it. Do you not see that Allah ‘azza wa-jall revealed verses that inspire hope after verses that inspire terror, and verses that inspire terror after verses that inspire hope. This is so that a slave (of Allah) remains both hopeful (of reward) and fearful (of punishment), without taking his own life, and without hoping for anything other than the truth from Allah ‘azza wa-jall. If you remember and preserve (apply) this advice of mine, then let no matter of the unseen world be more beloved to you than death - which, at any rate, is inevitable. And if you do not heed this advice of mine, then let no matter from the unseen world be more hateful to you than death."