Acts 1:24

Show us the one whom thou hast chosen (anadeixon on exelexw). First aorist active imperative of anadeiknumi, to show up, make plain. First aorist middle indicative second person singular of eklegw, to pick out, choose, select. In this prayer they assume that God has made a choice. They only wish to know his will. They call God the heart-searcher or heart-knower (kardiognwsta, vocative singular), a late word, here and Acts 15:8 only in the N.T. Modern physicians have delicate apparatus for studying the human heart.