This vocation to perfect love is not restricted to a small group of individuals. The invitation, "go, sell your possessions and give the money to the poor", and the promise "you will have treasure in heaven", are meant for everyone, because they bring out the full meaning of the commandment of love for neighbour, just as the invitation which follows, "Come, follow me", is the new, specific form of the commandment of love of God. Both the commandments and Jesus' invitation to the rich young man stand at the service of a single and indivisible charity, which spontaneously tends towards that perfection whose measure is God alone: "You, therefore, must be perfect, as your heavenly Father is perfect" (Mt 5:48). In the Gospel of Luke, Jesus makes even clearer the meaning of this perfection: "Be merciful, even as your Father is merciful" (Lk 6:36).
"Come, follow me" (Mt 19:21)
19. The way and at the same time the content of this perfection consist in the following of Jesus, sequela Christi, once one has given up one's own wealth and very self. This is precisely the conclusion of Jesus' conversation with the young man: "Come, follow me" (Mt 19:21). It is an invitation the marvellous grandeur of which will be fully perceived by the disciples after Christ's Resurrection, when the Holy Spirit leads them to all truth (cf. Jn 16:13).
It is Jesus himself who takes the initiative and calls people to follow him. His call is addressed first to those to whom he entrusts a particular mission, beginning with the Twelve; but it is also clear that every believer is called to be a follower of Christ (cf. Acts 6:1). Following Christ is thus the essential and primordial foundation of Christian morality: just as the people of Israel followed God who led them through the desert towards the Promised Land (cf. Ex 13:21), so every disciple must follow Jesus, towards whom he is drawn by the Father himself (cf. Jn 6:44).
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As he calls the young man to follow him along the way of perfection, Jesus asks him to be perfect in the command of love, in "his" commandment: to become part of the unfolding of his complete giving, to imitate and rekindle the very love of the "Good" Teacher, the one who loved "to the end". This is what Jesus asks of everyone who wishes to follow him: "If any man would come after me, let him deny himself and take up his cross and follow me" (Mt 16:24).
21. Following Christ is not an outward imitation, since it touches man at the very depths of his being. Being a follower of Christ means becoming conformed to him who became a servant even to giving himself on the Cross (cf. Phil 2:5-8). Christ dwells by faith in the heart of the believer (cf. Eph3:17), and thus the disciple is conformed to the Lord. This is the effect of grace, of the active presence of the Holy Spirit in us.
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As he calls the young man to follow him along the way of perfection, Jesus asks him to be perfect in the command of love, in "his" commandment: to become part of the unfolding of his complete giving, to imitate and rekindle the very love of the "Good" Teacher, the one who loved "to the end". This is what Jesus asks of everyone who wishes to follow him: "If any man would come after me, let him deny himself and take up his cross and follow me" (Mt 16:24).
21. Following Christ is not an outward imitation, since it touches man at the very depths of his being. Being a follower of Christ means becoming conformed to him who became a servant even to giving himself on the Cross (cf. Phil 2:5-8). Christ dwells by faith in the heart of the believer (cf. Eph3:17), and thus the disciple is conformed to the Lord. This is the effect of grace, of the active presence of the Holy Spirit in us.
from Veritatis Splendor