The gospel is for admitted failures, for confessed incompetents, in short, for people like all of us when we are honest. The incomprehension and incompetence, almost the rudeness and even perhaps the slight contempt detectible in both Nicodemus and the Samaritan Woman may all be intended by John to say to readers: Jesus’ promises are for problematic people; get used to it; be grateful.

Bruner, F. D. (2012). The Gospel of John: A Commentary (p. 250). Grand Rapids, MI;Cambridge, U.K.: Eerdmans.