9 Jesus' concern in this beatitude is not with the peaceful but with the "peacemakers." "Peace" is of constant concern in both OT and NT (e.g., Isa 52:7; Eph 2:11-22; Heb 12:14). The making of peace itself has messianic overtones (cf. "Prince of Peace" in Isa 9:6-7). Jesus does not limit the peacemaking to only one kind, and neither will his disciples. In the light of the Gospel, Jesus himself is the supreme peacemaker, making peace between God and us (Eph 2:15-17; Col 1:20) and among human beings. Our peacemaking will include the promulgation of that Gospel. It must also extend to seeking all kinds of reconciliation. Those who undertake this work are acknowledged as God's "sons". In the OT, Israel has the title "sons" (Dt 14:1; Hos 1:10). Now it belongs to the heirs of the kingdom who are especially equipped for peacemaking and so reflect something of the character of their heavenly Father.

12 The word "therefore" probably refers to the entire body of the sermon (5:17-7:12), for here there is a second reference to "the Law and the Prophets" (see comment on 5:17); Jesus stresses that he has taught about the true direction in which the OT law points, i.e., the Golden Rule. This rule sums up the Law and the Prophets (cf. Ro 13:9). In the context of fulfilling the Scriptures, it provides a handy summary of the righteousness to be displayed in the kingdom (cf. 5:20).

The verb translated "sums up" (lit., "is") might properly be translated "fulfills," as in Ac 2:16. In the deepest sense, therefore, the rule is the Law and the Prophets in the same way as the kingdom is the fulfillment of all that the Law and the Prophets foretold.

5:22 anyone who is angry. The law limited sin, but Jesus’ kingdom demands go deeper; the law said, “You shall not murder,” but Jesus demanded, “You shall not want to murder.” Some other ancient teachers agreed that desiring to kill someone revealed the same sort of heart that actually could commit murder. The insult, “Raca” (essentially meaning, “empty,” “devoid of value”) was roughly equivalent to the common insult, “Fool.” The punishments might also be equivalent, if the “judgment” and the “court” refer to the tradition, attested in later Jewish literature, of a heavenly court (cf. vv. 25 – 26). Jesus’ word for “hell” here is a Greek rendering of Gehinnom (Gehenna), a place of fiery torment for the damned (see note on 3:12); by adding explicit mention of “fire,” Jesus underlines the warning even more strongly. Jesus might have employed an element of hyperbole to drive home the point (cf. his use of “fools” in 23:17).