Note: this is a tentative suggestion. Verse 2 has three conditions, the third of which has to do with speaking. verse three is about using the tongue. The second condition is working righteousness and verse 4 is about true measures of right and wrong. The first condition is walking uprightly and verse 5 gives two examples. Does this stand up?
1 {A Psalm of David.}
A. LORD, who shall abide in thy tabernacle? who shall dwell in thy holy hill?
a. 2 He that walketh uprightly,
b. and worketh righteousness,
c. and speaketh the truth in his heart.
c’. 3 He that backbiteth not with his tongue,
nor doeth evil to his neighbour,
nor taketh up a reproach against his neighbour.
b’. 4 In whose eyes a vile person is contemned;
but he honoureth them that fear the LORD.
He that sweareth to his own hurt, and changeth not.
a’. 5 He that putteth not out his money to usury,
nor taketh reward against the innocent.
A’. He that doeth these things shall never be moved.
There is definitely something there, what you’ve suggested looks good to me, as they do seem to be thematic contrasts.
The one thing I wonder is whether “speaketh the truth in his heart” and “sweareth to his own hurt, and changeth not” could be linked? That could make it quite messy though.
Of course the chiasm doesn’t have to be that complex, it could be seen as only an ABBA structure, but I do like the way you’ve done it, I think it makes sense.
My understanding of the chiastic form of this psalm looks like this:
A who shall abide… who shall dwell
B he that walketh uprightly
C worketh righteousness
D speaketh truth
E backbiteth not
F nor does evil
G nor taketh up reproach
F’ vile person contemned
E’ honoreth them that fear
D’ sweareth to own hurt
C’ putteth not out to usury
B’ taketh reward against innocent
A’ never be moved