5335. And Joseph was a son of thirty years. That this signifies a full state of remains, is evident from the signification of "thirty," as being full of remains (of which below); and from the signification of "years," as being states (see n. 482, 487, 488, 493, 893). The number "thirty" in the Word signifies somewhat of combat, and it also signifies full of remains. The reason why it has this twofold signification, is that it is composed of five and six multiplied together, and also of three and ten so multiplied. From five multiplied by six it signifies somewhat of combat (n. 2276), because "five" signifies somewhat (n. 4638, 5291), and "six" combat (n. 720, 730, 737, 900, 1709); but from three multiplied by ten it signifies full of remains, because "three" signifies what is full (n. 2788, 4495), and "ten" remains (n. 576, 1906, 2284); that a compound number involves the like as its components, see n. 5291. (That remains are the truths joined to good stored up by the Lord in man's interiors, see n. 468, 530, 560, 561, 576, 660, 1050, 1738, 1906, 2284, 5135.)
[2] A fullness of remains is signified also by "thirty," by "sixty," and by a "hundred," in Mark:
The seed that fell into the good ground yielded fruit that sprang up and increased, and brought forth, one thirty, and another sixty, and another a hundred (Mark 4:8, 20);
as all these numbers arise from ten by multiplication, they signify a fullness of remains. And as man cannot be regenerated, that is, be admitted to the spiritual combats through which regeneration is effected, until he has received remains to the full, it was ordained that the Levites should not do any work in the tent of meeting until they had completed thirty years, which work or function is also called "warfare," as we read in Moses:
Take the sum of the sons of Kohath from the midst of the sons of Levi, from a son of thirty years and upward to a son of fifty years, everyone that cometh to the warfare, to do the work in the tent of meeting (Num. 4:2-3).
Something similar is said of the sons of Gershon, and of the sons of Merari (Num. 4:22-23, 29-30, 35, 39, 43). The like is involved in David's being thirty years old when he began to reign (2 Sam. 5:4).
[3] From all this it is now plain why the Lord did not manifest Himself until He was thirty years of age (Luke 3:23); for He was then in the fullness of remains. But the remains the Lord had He Himself procured for Himself, and they were of the Divine; and by means of them He united the Human essence to the Divine essence, and made the Human essence Divine (n. 1906). From Him then it is that "thirty years" signify a full state as to remains, and that the priests the Levites entered upon their functions when they were thirty years old, and that David, because he was to represent the Lord as to the royalty, did not begin to reign until he was thirty; for every representative is derived from the Lord, and therefore every representative looks to the Lord.