CCC 782 The People of God is marked by characteristics that clearly distinguish it from all other religious, ethnic, political, or cultural groups found in history:
– It is the People of God: God is not the property of any one people. But he acquired a people for himself from those who previously were not a people: “a chosen race, a royal priesthood, a holy nation.”1
– One becomes a member of this people not by a physical birth, but by being “born anew,” a birth “of water and the Spirit,”2 that is, by faith in Christ, and Baptism.
– This People has for its Head Jesus the Christ (the anointed, the Messiah). Because the same anointing, the Holy Spirit, flows from the head into the body, this is “the messianic people.”
– “The status of this people is that of the dignity and freedom of the sons of God, in whose hearts the Holy Spirit dwells as in a temple.”
– “Its law is the new commandment to love as Christ loved us.”3 This is the “new” law of the Holy Spirit.4
– Its mission is to be salt of the earth and light of the world.5 This people is “a most sure seed of unity, hope, and salvation for the whole human race.”
-Its destiny, finally, “is the Kingdom of God which has been begun by God himself on earth and which must be further extended until it has been brought to perfection by him at the end of time.”6

CCC 1337 The Lord, having loved those who were his own, loved them to the end. Knowing that the hour had come to leave this world and return to the Father, in the course of a meal he washed their feet and gave them the commandment of love.7 In order to leave them a pledge of this love, in order never to depart from his own and to make them sharers in his Passover, he instituted the Eucharist as the memorial of his death and Resurrection, and commanded his apostles to celebrate it until his return; “thereby he constituted them priests of the New Testament.”8

CCC 1823 Jesus makes charity the new commandment.9 By loving his own “to the end,”10 he makes manifest the Father’s love which he receives. By loving one another, the disciples imitate the love of Jesus which they themselves receive. Whence Jesus says: “As the Father has loved me, so have I loved you; abide in my love.” And again: “This is my commandment, that you love one another as I have loved you.”11

CCC 1970 The Law of the Gospel requires us to make the decisive choice between “the two ways” and to put into practice the words of the Lord.12 It is summed up in the Golden Rule, “Whatever you wish that men would do to you, do so to them; this is the law and the prophets.”13
The entire Law of the Gospel is contained in the “new commandment” of Jesus, to love one another as he has loved us.14

CCC 2196 In response to the question about the first of the commandments, Jesus says: “The first is, ‘Hear, O Israel: The Lord our God, the Lord is one; and you shall love the Lord your God with all your heart, and with all your soul, and with all your mind, and with all your strength.’ The second is this, ‘You shall love your neighbor as yourself.’ There is no other commandment greater than these.”15
The apostle St. Paul reminds us of this: “He who loves his neighbor has fulfilled the law. The commandments, ‘You shall not commit adultery, You shall not kill, You shall not steal, You shall not covet,‘ and any other commandment, are summed up in this sentence, ‘You shall love your neighbor as yourself.’ Love does no wrong to a neighbor; therefore love is the fulfilling of the law.”16

CCC 2822 Our Father “desires all men to be saved and to come to the knowledge of the truth.”17 He “is forbearing toward you, not wishing that any should perish.”18 His commandment is “that you love one another; even as I have loved you, that you also love one another.”19 This commandment summarizes all the others and expresses his entire will.

CCC 2842 This “as” is not unique in Jesus’ teaching: “You, therefore, must be perfect, as your heavenly Father is perfect”; “Be merciful, even as your Father is merciful”; “A new commandment I give to you, that you love one another, even as I have loved you, that you also love one another.”20 It is impossible to keep the Lord’s commandment by imitating the divine model from outside; there has to be a vital participation, coming from the depths of the heart, in the holiness and the mercy and the love of our God. Only the Spirit by whom we live can make “ours” the same mind that was in Christ Jesus.21 Then the unity of forgiveness becomes possible and we find ourselves “forgiving one another, as God in Christ forgave” us.22

1 1 Pet 2:9.
2 Jn 3:3-5.
3 Cf. Jn 13 34
4 Rom 8:2; Gal 5:25.
5 Cf. Mt 5:13-16.
6 LG 9 # 2.
7 Cf. Jn 13:1-17; 34-35.
8 Council of Trent (1562): DS 1740.
9 Cf. Jn 13:34.
10 Jn 13:1.
11 Jn 15:9, 12.
12 Cf. Mt 7:13-14,21-27.
13 Mt 7:12; cf. Lk 6:31.
14 Cf. Jn 15:12; 13:34.
15 Mk 12:29-31; cf. Deut 6:4-5; Lev 19:18; Mt 22:34-40; Lk 10:25-28.
16 Rom 13:8-10.
17 1 Tim 2:3-4.
18 2 Pet 3:9; cf. Mt 18:14.
19 Jn 13:34; cf. 1 Jn 3; 4; Lk 10:25-37.
20 Mt 5:48; Lk 6:36; Jn 13:34.
21 Cf. Gal 5:25; Phil 2:1,5.
22 Eph 4:32.