Verses 15-20 deal with false prophets, but verses 21-23 deal with false followers. The repeated cry of these false followers reveals their fervency.
"In Jesus' day it is doubtful whether Lord' when used to address him meant more than teacher' or sir.' But in the postresurrection period, it becomes an appellation of worship and a confession of Jesus' deity."352
Obedience to the Father's will determines entrance into the kingdom, not professed admiration for Jesus. This is the first occurrence of the phrase "my Father"in Matthew. By using it Jesus was implicitly claiming to be the authoritative revealer of God. During Jesus' ministry doing the will of God boiled down to believing that Jesus was the Messiah and responding appropriately (John 6:29).353Note that entrance into the kingdom was still future. The kingdom was not yet present. Judgment will precede entrance into the kingdom.
Jesus claimed to be the eschatological Judge. This was one of Messiah's functions. "That day"(v. 22) is the day Jesus will judge false professors. It is almost a technical term for the messianic age (cf. Isa. 2:11, 17; 4:2; 10:20; Jer. 49:22; Zech. 14:6, 20-21). "In your name"means as your representatives and claiming your authority. Obviously it was possible for false disciples to prophesy, exorcise demons, and perform miracles in Jesus' name (e.g., Judas Iscariot). The authority of His name (reputation) enabled them to do so, not their own righteousness or relationship to Him. Many onlookers undoubtedly viewed these works as good fruit and evidence of righteous character. However these were cases of tares that looked like wheat (cf. 13:24-30).
Jesus Himself would sentence the hypocrites to depart from His presence (v. 23).354Thus Jesus claimed again that He is the Judge who will determine who will enter the kingdom and who will not. This was a decidedly messianic function. The quotation from Psalm 6:8 puts Jesus in the place of the sufferer whom God has vindicated and who now tells those who have done Him evil to depart from His presence. Moreover He will say He never knew these false professors. Many people deal with holy things daily yet have no personal acquaintance with God because they are hypocrites. It is their failure to bow before divine law, the will of God, that renders them practitioners of lawlessness and guilty.