G2480–ἰσχύω–ischuō

For a testament is of force after men are dead: otherwise it is of no strength at all while the testator liveth.

ἰσχύει ischuei “it is in force”

Confess your faults one to another, and pray one for another, that ye may be healed. The effectual fervent prayer of a righteous man availeth much.

ἰσχύει ischuei “prevails”

And prevailed not; neither was their place found any more in heaven.

ἴσχυσεν, ischusen “he had [enough] strength,”