Hitbodedut is a basic spiritual practice recommended by many hasidic rebbes. It is a centerpiece of the way to God taught by Rabbi Nachman of Bratzlav.
Hitbodedut literally means "self-seclusion," and is best accomplished in an isolated place where there are no people and where you can be truly alone with yourself and with God. Setting a specific time for this "aloneness" is of the essence, for we are saying, "God, I am now going to dedicate this amount of time to being just with You." Thus, Rabbi Nachman praises just sitting "with Him," even when you cannot open your mouth. If you dedicate some time to sit and be with God, then you are with Him even if you are silent.— Yitzhak Buxbaum in Jewish Spiritual Practices