When establishing a new temple space in your home, or consecrating a new space in which you will invoke your Holy Guardian Angel or some other expression of the presence of divinity, the space should first be properly cleaned, then prepared with its furnishings. Before the lamp is lit and the divine is called in, this blessing may be used to make the space ready.
Divine Light, Immovable Mover, Limitlessness who is wholly present and wholly active in every place created and uncreated; hearken to this earnest prayer, and be the sanctity of this dwelling. Let no vileness of hostile powers prevail here, let no falsehood deter those herein, but by the working of the Holy Guardian Angel may a faultless service always be rendered to the Work in this place, and a holy liberty abound; through the light of the Lord Most Secret.
This blessing draws from the method given in The Roman Ritual of the Roman Catholic Church, updated and amended for more Gnostic and Thelemic purposes.