9933. And thou shalt put it upon a thread of blue. That this signifies influx into the truth of celestial love, is evident from the signification of "blue," as being the truth of celestial love (of which below). Influx into this truth is signified by the plate on which was engraved "Holiness to Jehovah" being put upon a thread of blue, for in this way it hung from it and was bound to it, and in the spiritual sense by "being bound to," and "hanging," is signified to inflow, because all conjunction whatever is effected by means of influx. That the influx is into the truth of celestial love about the Lord's Divine Human, which is signified by "Holiness to Jehovah," is because in that sphere of heaven where is the truth of celestial love, no other Divine is perceived than the Divine Human of the Lord.
 For the case herein is as follows. There are three heavens, which have been distinguished from one another by means of the degrees of good. In the inmost heaven is the good of celestial love, which is the good of love to the Lord; in the second or middle heaven is the good of spiritual love, which is the good of charity toward the neighbor; in the first or ultimate heaven is the good of natural love, from spiritual and from celestial love, which is the good of faith and obedience. In each heaven there is an internal and an external. As just said, the internal in the inmost heaven is the good of love to the Lord, and the external there is the good of mutual love, which belongs to the love of good for the sake of good. This good is what is meant by the truth of celestial love, which is signified by "the thread of blue." In the sphere where is this truth, the Lord's Human is perceived as being the Divine Itself in the heavens, and therefore as soon as an angel is raised into this sphere, he comes into this light also. This perception flows in from the Lord, because the Divine Human of the Lord makes heaven. This is the influx which is here signified. (That "blue" denotes the celestial love of truth, or what is the same thing, the truth of celestial love, see n. 9466, 9687, 9833.)