(from Simon)
A (1a) Then shall the kingdom of heaven be likened unto ten virgins,
B (1b) which took their lamps,
C (1c) and went forth to meet the bridegroom.
D (2a) And five of them were wise,
E (2b) and five were foolish.
E’ (3) They that were foolish took their lamps, and took no oil with them:
D’ (4) But the wise took oil in their vessels with their lamps.
C’ (5-6) While the bridegroom tarried, they all slumbered and slept. And at midnight there was a cry made, Behold, the bridegroom cometh; go ye out to meet him.
B’ (7-9) Then all those virgins arose, and trimmed their lamps. And the foolish said unto the wise, Give us of your oil; for our lamps are gone out. But the wise answered, saying, Not so; lest there be not enough for us and you: but go ye rather to them that sell, and buy for yourselves.
A’ (10-12) And while they went to buy, the bridegroom came; and they that were ready went in with him to the marriage: and the door was shut. Afterward came also the other virgins, saying, Lord, Lord, open to us. But he answered and said, Verily I say unto you, I know you not. (13) Watch therefore, for ye know neither the day nor the hour wherein the Son of man cometh.
This Parable also seems to parallel the Song of Solomon chapters 3 (wise virgin) and 5 (foolish one).
This “check mark” style chiastic structure (with half the structure acting as basically a “table of contents” for the larger second half) is also seen in the book of Romans, where (after the intro) 1:8-18 summarize and form a reasoned outline for the rest of the epistle. Search and see – the structure can viewed on my web site.
Your text above is based on the KJV which differs from the Greek (UBS, 3rd Edition). In the Greek 2(a) is foolish and 2(b) wise. This renders your structure wrong.
A chiasm seems evident in verses 1-5 Maidens bridegroom bridegroom and all (referencing the maidens). This chiasm then ‘crosses’ the difference between the two sets of maidens.
Verses 6 then introduces the second section introducing the bridegroom as the main actor in verses 7-12 and the results of the maidens prepared and not prepared.
7-9 refer to action between the two groups themselves and 10-12 between the bridegroom and the the two sets of maidens with end results for each group.
13 then forms a conclusion for the whole section.
The section (1-13) as a whole therefor only has a chiasm in verses 1-5.
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