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Study Dictionary
Impossible
IMPOSSIBLE [ISBE]
IMPOSSIBLE - im-pos'-i-b'-l (verb adunateo; adjective adunatos): "To be impossible" is the translation of adunateo, "to be powerless," "impotent" (Mt 17:20; Lk 1:37, the Revised Version (British and American) "void of power") adunatos, "powerless," etc., is translated "impossible" Mt 19:26; Mk 10:27; Lk 18:27; Heb 6:4,18; 11:6; "impossible" in Heb 6:4 is in the Revised Version (British and American) transferred to 6:6); anendektos, "not to be received" or "accepted," is also translated "impossible" (Lk 17:1). In several of these passages it is affirmed that "nothing is impossible with God," but, of course, this means nothing that is consistent with the Divine nature, e.g. (as Heb 6:18) it is not possible for God to lie. So, when it is said that nothing is impossible to faith, the same limitation applies and also that of the mind or will of God for us. But much more is possible to a strong faith than a weak faith realizes, or even believes.W. L. Walker
Also see definition of "Impossible" in Word Study