Addressing the OP, Agreed, 100%, scripture, Jeremiah 11:20 " But, O LORD of hosts, that judgest righteously, that triest the reins and the heart, let me see thy vengeance on them: for unto thee have I revealed my cause."
the OT, "LORD", who is God he, "triest the reins and the heart".
the NT, "Lord", who is God he, "triest the reins and the heart".
Revelation 2:23 " And I will kill her children with death; and all the churches shall know that I am he which searcheth the reins and hearts: and I will give unto every one of you according to your works."
Same one person.
PICJAG, 101G.