The small chiasm in Deuteronomy 26:14 concerns bringing tithes of the land to God and ensuring that those tithes are brought in a condition that honors God and can be accepted by him.
- I have not eaten of my tithes while in mourning (for the dead)
- I have not stored away any of these tithes while unclean
- I have not given any of my tithes for the dead
Spiritual uncleanness results from contact with death, whether through the loss of life force (e.g. menstruation and other sexual discharges and dysfunctions), through the loss of life itself (e.g. physical contact with the dead or their graves), or through spiritual association with death (e.g. ancestor worship, necromancy, and the honoring of false gods). This is why uncleanness is sandwiched between mourning and death. Anything dedicated to God should not be contaminated with unclean things and activities, not because they are sinful--some are and some aren't--but because God is most holy.
Uncleanness is the opposite of holy. It interferes with our spiritual communion with him, which is a possible reason that God says the flesh of pigs and other unclean animals is abhorrent to him and ought to be to us. He likes to spend time with us and spiritual uncleanness gets in the way.
This chiasm is immediately followed by a couplet (a simple, 2-part parallelism):
- I have hearkened
- To the voice of God
- I have done
- What God has commanded
To truly hear God is to obey. It doesn't matter if what God says makes sense to us or not. He always has reasons, and he is under no obligation to explain them to us. Our job is to trust him and to love him, and both trust and love require obedience to his commands. If God doesn't want his tithes tainted with death and mourning, then we need to make sure we give cheerfully and without reference to the dead.
Not even to the "sainted" dead.