Translation
and I will kill her children with death. Then all the churches will know
Go to footnote numberthat I am the one who searches the kidneys and the heart,
Go to footnote numberand I will give to each of you according to your works.
Paraphrase
and I will kill her children stone dead. Then all the churches will know that I am the one who searches both the affections that drive decision-making, and the real person deep down inside, and I will give to each of you according to your works.
Footnotes
1: “all the churches will know.”
At first it seems strange that this act would serve as a demonstration to the church instead of the world. However, this vision is intended as encouragement for those in persecution, and it would be received as encouragement for them to know that God tests each heart and judges accordingly. Their hearts are pure so they have no need to worry, and this confirms to them that those who are oppressing them will also have to face the consequences of their actions.
2: “the kidneys and the heart:”
Both refer to the inner being and the will. The word “kidneys” referred to the center of emotions, while the “heart” was considered the center of the thoughts and feelings. It is a repeating of the same thing, a doubly-strong way of referring to who we really are deep down inside.