ISB ~ Matthew 5 v48

You … must be perfect:Jesus advocates moral righteousness higher than the Old Covenant—it is a standard of mercy. Just as Israel was to imitate God in being “holy” (Lev 19:2), so Jesus calls the Church to imitate God’s perfect compassion (Lk 6:36). The Father is kind and merciful to the good and evil alike, so his children must extend mercy even to their enemies (5:7; Lk 10:29-37; Jas 2:13). See note on Lk 6:36(CCC 1968, 2842).