That prophet (tou prophtou ekeinou). Emphasizes the future prophet as on "him" (autou) before "hearken." They had refused to "hearken" to Moses and now, alas, many had refused to "hearken" to Christ. Shall be utterly destroyed (exoleqreuqhsetai). First future passive of exole- (o) qreuw, a late verb, to destroy utterly (ex), only here in the N.T., common in the LXX.