While discussing eternal rewards in His Sermon on the Mount (Matt 5:1-2, 12, 46; 6:1-6, 16-18), Jesus taught there would be varying degrees of placement in the kingdom of heaven. In Matthew 5:19, Jesus said, “whoever breaks one of the least of these commands and teaches others to do so will be called least in the kingdom of heaven. But whoever practices and teaches these commands will be called great in the kingdom of heaven.” In this verse, Jesus talked about two kinds of saved people, both of which will be “in the kingdom of heaven.” This is plainly understood from what Jesus said. The first group will be believers who, after salvation, live a life of disobedience to God, rebelling against His Word, and teaching others to do the same. These disobedient-to-the-Word believers will forfeit eternal rewards and have a low status in heaven. Jesus calls them least, which translates the Greek word ἐλάχιστος elachistos, which refers to being “the lowest in status, least…being considered of very little importance, insignificant.” The second group of believers will be those who live a life of obedience to God, learning and doing His Word, and teaching others to do the same. These obedient-to-the-Word believers will be rewarded by God and be blessed with a high status in heaven. Jesus calls these great, which translates the Greek word μέγας megas, which in this passage refers to being “great in dignity, distinguished, eminent, illustrious.” This gradation of status in heaven is taught elsewhere by Jesus (Matt 11:11; 18:1-4; 20:20-28). To be clear, Jesus is not addressing salvation in the Sermon on the Mount (Matthew chapters 5-7); rather, He’s addressing the demands of discipleship and rewards. Click here for a complete set of notes: Great and Least in the Kingdom of Heaven - A Life of Discipleship.
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 William Arndt et al., A Greek-English Lexicon of the New Testament and Other Early Christian Literature (Chicago: University of Chicago Press, 2000), 314.
 William D. Mounce, Mounce’s Complete Expository Dictionary of Old & New Testament Words (Grand Rapids, MI: Zondervan, 2006), 1207.