He measured the wall of the holy Jerusalem, a hundred and
     forty and four cubits, the measure of a man, which is that
     of an angel (21:17).

“Jerusalem” means here the Lord’s church, and in a more eminent sense, heaven;{1} the “wall” means truth, which is a defence against the assault of falsities and evils;{2} “a hundred and forty and four” means all goods and truths in the complex;{3} “measure” means what a thing is,{4} a “man” means one in whom are goods and truths in general and in particular, thus in whom is heaven.  And as it is from this that an angel is a man, it is said “the measure of a man, which is that of an angel.”  This is the spiritual meaning of these words.  Without that meaning how could it be seen that “the wall of the Holy Jerusalem” is “the measure of a man, which is that of an angel?"{5}

  {Footnote 1} “Jerusalem” means the church (n. 402, 3654, 9166).

  {Footnote 2} The “wall” means truth defending against the
  assault of falsities and evils (n. 6419).

{Footnote 3} “Twelve” means all truths and goods in the complex (n. 577, 2089, 2129, 2130, 3272, 3858, 3913).  Likewise “seventy-two,” and “a hundred and forty-four,” since this comes from twelve multiplied into itself (n. 7973).  All numbers in the Word signify things (n. 482, 487, 647, 648, 755, 813, 1963, 1988, 2075, 2252, 3252, 4264, 4495, 5265).  Multiplied numbers have a like signification as the simple numbers from which they arise by multiplication (n. 5291, 5335, 5708, 7973).

  {Footnote 4} “Measure” in the Word signifies the quality of a
  thing in respect to truth and good (n. 3104, 9603).

  {Footnote 5} In regard to the spiritual or internal sense of
  the Word see the explanation of The White Horse in the
  Apocalypse, and the Appendix to The Heavenly Doctrine.

74.  Let us now turn to experience.  That angels are human forms, or men, has been seen by me a thousand times.  I have talked with them as man with man, sometimes with one, sometimes with many together; and I have seen nothing whatever in their form different from the human form; and have occasionally been surprised to find them such.  And that this might not be said to be a delusion or a vision of fancy, I have been permitted to see angels when fully awake or in possession of all my bodily senses, and in a state of clear perception.  And I have often told them that men in the Christian world are in such blind ignorance in regard to angels and spirits as to believe them to be minds without form, even pure thoughts, of which they have no idea except as something ethereal in which there is some vitality.  And as they thus ascribe to angels nothing human except a thinking faculty, they believe that having no eyes they do not see, having no ears they do not hear, and having no mouth or tongue they do not speak. [2] To this the angels replied that they are aware that such a