The Isavasya Upanishad forms a part of the Sukla Yajur Veda, occuring in fact, as an integral part of the initial Samhita portion, making it an exception to the general feature of the Upanishads occuring towards the end of their respective Vedas. This Upanishad is considered specially important because of this special feature. Its importance also derives from many of its central ideas finding endorsement and elaboration in the Gita. This Upanishad starts with the word "Isa" or God, and therefore takes its name from this word. This Upanishad is quite a short one, comprised of just 18 stanzas.