The Exegetical Anatomy of Kidneys

Psalm 73:21

In Psalm 73 Asaph wrote about the judgment and destruction of the wicked.  For a time, Asaph admired the wicked and their place in life. Then he contemplated their end, because God will bring judgment upon them. Asaph was grieved in his heart. 1Asaph used the term “heart” (“לְבָבִ֑י”–noun, masculine singular construct, suffix first common singular) to describe the place of his grief (“יִתְחַמֵּ֣ץ”(–hithpael imperfect third masculine singular). The judgment and destruction of the wicked compelled the heart of Asaph to grief. Likewise, in his kidneys, he was vexed. 2Asaph used the term “my kidneys” (כִלְיוֹתַ֗י–noun feminine plural construct, suffix first common singular) to described the place “I was vexed” (hithpael imperfect, first common singular). The hithpael stems here emphasize the causative intensive action. Because the hithpael stem suggests intensive reflexive action, we know that the external reality of judgment had psychological effects upon Asaph spiritually related to two separate spiritual organs. His heart was struck with grief and his kidneys were vexed. Therefore, we should keep the exegetical term “heart” separate from the term for “kidneys.” 

In the Pentateuch the term “kidneys” can refer to physical organs (Exodus 29:13; 29:22; Leviticus 3:4; 3:10; 3:15; 4:9; 7:4; 8:16; 8:25; 9:19; Deuteronomy 32:14). In other places outside the Pentateuch, we see the psychological aspects of the term for kidneys. In Job 16:13, Job said that God used His arrows to split his kidneys wide open. In Job 19:27, his kidney yearns to see God. In Psalm 7:9, David explained that God tests the hearts and kidneys. In Psalm 16:7, Yahweh gave David counsel and then in the night David’s kidney chastened him. In Psalm 26:2, David asked Yahweh to examine him and refine “my kidney and my heart.” In Psalm 139:13, David acknowledged that Yahweh formed his kidneys while in his mother’s womb. In Proverbs 23:16, we read that “my kidney” will exult  when your lips speak upright things.