'Tester' in the Bible

The heating-pot is for silver and the oven-fire for gold, but the Lord is the tester of hearts.

Every way of a man seems right to himself, but the Lord is the tester of hearts.

If you say, See, we had no knowledge of this: does not the tester of hearts give thought to it? and he who keeps your soul, has he no knowledge of it? and will he not give to every man the reward of his work?

I have made you a tester among my people, so that you may have knowledge of their way and put it to the test.

I the Lord am the searcher of the heart, the tester of the thoughts, so that I may give to every man the reward of his ways, in keeping with the fruit of his doings.