The encounter with Christ radically changes a person's life, spurs him to metanoia or a profound conversion of mind and heart, and establishes a communion of life which becomes discipleship. In the Gospels, the following of Christ is expressed in two attitudes: the first consists in "going with" Christ (akolouthein); the second, in "walking behind" the One who leads, following in his footsteps and direction (erchesthai opiso). This gives rise to the figure of the disciple, which is realized in different ways. Some follow him in a still general and often superficial way, like the crowd (cf. Mk 3: 7; 5: 24; Mt 8: 1, 10; 14: 13; 19: 2; 20: 29). There are sinners (cf. Mk 2: 14-15); the women who support Jesus' mission with their practical service are mentioned several times (cf. Lk 8: 2-3; Mk 15: 41). Some receive a specific calling from Christ, and among them a special place is reserved for the Twelve.
The typology of those called is thus quite varied: people involved in fishing and tax collectors, the honest and sinners, the married and the single, the poor and the wealthy, such as Joseph of Arimathea (cf. Jn 19: 38), men and women. There is even Simon the Zealot (cf. Lk 6: 15), that is, a member of the anti-Roman revolutionary opposition. And there were some who refused the invitation, like the rich young man who, at Christ's demanding words, was saddened and went away sorrowful, "for he had great possessions" (Mk 10: 22).
The conditions for taking the same way as Jesus are few but fundamental. As we heard in the Gospel passage read a few moments ago; it is necessary to turn one's back on the past and make a clean break with it, a metanoia in the profound sense of the word: a change of mind and life.
Christ proposes a narrow way that demands sacrifice and total self-giving: "If any man would come after me, let him deny himself and take up his cross and follow me" (Mk 8: 34). It is a way that includes the thorns of suffering and persecution: "If they persecuted me, they will persecute you ... also" (Jn 15: 20). It is one which makes missionaries and witnesses to Christ's word, but demands that his apostles take "nothing for their journey ... no bread, no bag, no money in their belts" (Mk 6: 8; cf. Mt 10: 9-10).
Discipleship, then, is not an easy journey on a level road. It can include moments of hardship to the point that on one occasion "many of his disciples drew back and no longer went about with him" (Jn 6: 66), that is, with Jesus, who was compelled to challenge the Twelve with a crucial question: "Will you also go away?" (Jn 6: 67). On another occasion, when Peter himself rebels against the prospect of the Cross, he is abruptly rebuked in words that, according to the nuance of the original text, could be an invitation to get "behind" Jesus again, after trying to reject the goal of the Cross: "Get behind me, Satan! For you are not on the side of God, but of men" (Mk 8: 33).
The risk of betrayal will be lurking for Peter who in the end, however, would follow his Master and his Lord with the most generous love. Peter, in fact, will make his profession of love on the shores of the Sea of Tiberias: "Lord, you know everything; you know that I love you". And Jesus will tell him "by what death he was to glorify God", adding twice, "Follow me!" (Jn 21: 17, 19, 22).
Discipleship is expressed in a special way in the beloved disciple, who enters into intimacy with Christ, receives his Mother as a gift and recognizes him after he has risen (cf. Jn 13: 23-26; 18: 15-16; 19: 26-27; 20: 2-8; 21: 2, 7, 20-24).
The ultimate goal of discipleship is glory. The way is one of "imitating Christ", who lived in love and died for love on the Cross. The disciple "must, so to speak, enter into Christ with all his own self, he must "appropriate' and assimilate the whole of the reality of the incarnation and redemption in order to find himself" (Redemptor hominis, n. 10). Christ must enter into his ego to free him from selfishness and pride, as St Ambrose says in this regard: "May Christ enter your soul, may Jesus dwell in your thoughts, to prevent sin from having any room in the sacred tent of virtue" (Comment on Psalm 118, letter "daleth", 26).
The Cross, sign of love and of total self-giving, is therefore the emblem of the disciple called to be configured to the glorious Christ. A Father of the Eastern Church, who was also an inspired poet, Romanus the Melodist, challenges the disciple in this way: "You have the Cross as your cane; rest all your youth on it. Bring it to your prayer, bring it to the common table, bring it with you to bed and everywhere, as your claim to glory.... Say to your spouse who is now joined to you: I throw myself at your feet. In your infinite mercy, give peace to your world, help to your Churches, concern to pastors and harmony to the flock, so that we may all sing of our resurrection forever" (Hymn 52 "To the newly baptized", strophes 19 and 22).