"I may live for thirty years, or perhaps forty, or maybe just one day: therefore I have resolved to use this day, or whatever I have to say in these thirty years or whatever I have to say this one day I may have to live — I have resolved to use it in such a way that if not one day in my whole past life has been used well, this one by the help of God will be. JP VIII 1 A 533"
January 1, 1970
https://en.wikiquote.org/wiki/S%C3%B8ren_Kierkegaard