This one is perhaps a bit speculative. I suggest that A and B share similar thoughts with A’ and B’ (wise and foolish choice of way with wise and foolish choice of foundation). The main difficulty though is F and F’, where we have two sections without a verbal connection (although there is an interesting contrast between gathering and casting).
A (13) Enter ye in at the strait gate: for wide is the gate, and broad is the way, that leadeth to destruction, and many there be which go in thereat:
B (14) Because strait is the gate, and narrow is the way, which leadeth unto life, and few there be that find it.
C (15) Beware of false prophets, which come to you in sheep’s clothing, but inwardly they are ravening wolves.
D (16a) Ye shall know them
E (16b) by their fruits.
F (16c) Do men gather grapes of thorns, or figs of thistles?
G (17a) Even so every good tree bringeth forth good fruit;
H (17b) but a corrupt tree bringeth forth evil fruit.
H’ (18a) A good tree cannot bring forth evil fruit,
G’ (18b) neither can a corrupt tree bring forth good fruit.
F’ (19) Every tree that bringeth not forth good fruit is hewn down, and cast into the fire.
E’ (20a) Wherefore by their fruits
D’ (20b) ye shall know them.
C’ (21-23) Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven. Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works? And then will I profess unto them, I never knew you: depart from me, ye that work iniquity.
B’ (24-25) Therefore whosoever heareth these sayings of mine, and doeth them, I will liken him unto a wise man, which built his house upon a rock: And the rain descended, and the floods came, and the winds blew, and beat upon that house; and it fell not: for it was founded upon a rock.
A’ (26-27) And every one that heareth these sayings of mine, and doeth them not, shall be likened unto a foolish man, which built his house upon the sand: And the rain descended, and the floods came, and the winds blew, and beat upon that house; and it fell: and great was the fall of it.