2 Bible Verses about God Searching Hearts

And God, who searches our hearts, knows what the Holy Spirit [has] in mind, because He [i.e., the Holy Spirit] goes to God on behalf of the saints [i.e., God's holy people] in harmony with God's will.

And I will strike her children dead [or, "kill her children by some terrible calamity" See Ex. 5:3 LXX]. Then all the churches will know that I am the One who searches the inmost being of people [Note: The Greek says, "searches the kidneys and hearts." In that day these internal organs stood for the inner thoughts, emotions, etc.]. And I will repay each one of you people according to what you have done.