Considering Oneself Dead Before Davening:
Rav Aharon of Kobrin zy”a (quoted in Bais Aharon, Seder Hayom) would say that before a tzadik would daven, he would imagine that he was dead and was suffering in the grave, and someone had come and said, “Get up and daven!”
He said that his own father, Rav Asher of Stolin zy”a, told him that he davened like this for a full year. (Sefer Tiferes Banim – Munkatch, Parshas Lech Lecha – writes that this idea can be used to explain the verse in Bereishis 17:11: “Hishalech lifanei v’heyei tamim. Walk before Me and be complete.” The Gemara says in Sotah 12A that the word “halicha” - to walk - always indicates death, as is seen from numerous sources. Thus, Hashem told Avrohom to imagine that he was already dead and lying in the grace and then to “be tamim”, meaning to get up and daven with complete
