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Study Dictionary
Importunity
IMPORTUNITY [ISBE]
IMPORTUNITY - im-por-tu'-ni-ti: Occurs only in Lk 11:8, where it is the rendering of anaideia (Westcott-Hort, anaidia). This Greek word implies an element of impudent insistence rising to the point of shamelessness which the English word "importunity" fails to express, thus weakening the argument of the parable, which is that if by shameless insistence a favor may be won, even from one unwilling and ungracious, still more surely will God answer the earnest prayer of His people. God's willingness to give exceeds our ability to ask. The parable teaches by way of contrast, not by parallel.David Foster Estes
Also see definition of "Importunity" in Word Study