These verses stand in close connexion with Matthew 7:15-20. Seeing that external actions are the result of internal life, it is they, not words nor even miracles, by which the true followers of Christ will be finally distinguished from others, and which therefore will alone secure admission to abiding with Christ in the kingdom of heaven.
To these verses Luke 13:23-28 have many resemblances (cf. also Luke 13:13, Luke 13:14, supra). St. Luke thus omits the warning against false teachers. (For verse 21, cf. also Luke 6:46.