When does the Christian community consider someone to be a “lost soul”? Because of hopelessness, not following religious commandments and possession? And how are such Christians treated?
The question consist of two parts. Firstly, (1), how does the Christian community, i.e. the church, treat its sinful members and those who deliberately turn away from it. And secondly, (2), how does it deal with ‘posession’?
Re (1.1.) The expression “lost soul” used in the question is found in contemporary language, however, from a Christian point of view it is misguided. The church speaks of sinful human beings. This includes all the baptised, who will always fall back into sin.
Firstly, it is true that: Only God forgives sins: Only God has the power to forgive sins (cf. Matthew 2:7). Because Jesus is God he says of himself “that the son of man has the authority to forgive sins here on earth” (Mark 2:10). He exercises this divine authority: “Your sins are forgiven” (Mark 2:5; Luke 7:48). Furthermore: thanks to his divine authority he in turn authorises human beings (John 20:21-23) to exercise it in his name. Christ wanted his church as a whole through its prayer, its life and its actions to be a sign and a tool for the forgiveness and reconciliation he brought about at the price of his blood. He trusted the authority to forgive sins in his name to the apostolic office. This office is instructed to offer the “service of forgiveness” (2 Corinthians 5:18). The apostles are sent “in the name of Christ”; through him God himself admonishes and pleads: “Be reconciled to God!” (2 Corinthians 5:20). During his public ministry Jesus not only forgave sins but also showed the consequences of forgiveness: He restored forgiven sinners to the community of God’s people, from which sin had distanced them or even removed them. A visible sign of this is that Jesus invites sinners to his table, that he even joins their table - an action which clearly and movingly expresses God’s forgiveness and the return to the community of the people of God. By granting the apostles the authority to forgive sins the Lord also grants them the authority to reconcile sinners with the church.” (cf. CCC Nos. 1441-1444)
Baptism is the first and most important sacrament for the forgiveness of sins; it unites the believer with the Christ who died and rose again and it bestows the Holy Spirit. The church offers the baptised members who are steeped in sin and guilt the sacrament of repentance and reconciliation. It is the special gift of the Lord to his church in order to achieve reconciliation. Sin is an insult to God and a break with communion with him. But it also impairs communion with the church. Jesus did not only forgive sins but he also authorised and commissioned the church to free people from their sins. Through the sacrament of repentance and reconciliation all believers are offered God’s forgiveness and reconciliation with the church (cf. CCC Nos. 981; 1440). “There is no offence, however serious, that the Church cannot forgive. "There is no one, however wicked and guilty, who may not confidently hope for forgiveness, provided his repentance is sincere. Christ who died for all men desires that in his Church the gates of forgiveness should always be open to anyone who turns away from sin (cf. Matthew 18:21-22). Catechesis ( = the teaching of the doctrine the faith of the church) strives to awaken and nourish in the faithful faith in the incomparable greatness of the risen Christ's gift to his Church: the mission and the power to forgive sins through the ministry of the apostles and their successors.” (Catechism of the Catholic Church, Nos. 982-983
(1.2) Certain particularly grave sins incur excommunication, the most severe ecclesiastical penalty, which impedes the reception of the sacraments and the exercise of certain ecclesiastical acts, and for which absolution consequently cannot be granted, according to canon law, except by the Pope, the bishop of the place or priests authorized by them. In danger of death any priest, even if deprived of faculties for hearing confessions, can absolve from every sin and excommunication.” (CCC, No. 1463)
(1.3.) In addition to the forgiving of sins the church is also commissioned with pastoral care. The service of forgiveness and reconciliation is one aspect of pastoral care. Even those not close to the church associate the term pastoral care positively as synonymous with a sense of responsibility, empathy, confidentiality, fidelity, courage. Pastoral care is not limited to members of the church. The church has been called by Christ to serve all people and to witness to the truth and the love of Christ to all. The pastoral role of the church therefore encompasses the whole mission of the church in the world. The pastoral constitution of the Second Vatican Council “on the church in the modern world”, Gaudium et Spes, begins with the following words: “The joys and the hopes, the griefs and the anxieties of the men of this age, especially those who are poor or in any way afflicted, these are the joys and hopes, the griefs and anxieties of the followers of Christ. Indeed, nothing genuinely human fails to raise an echo in their hearts.” This concerns the task of the whole people of God, which is carried out by each individual member according to their charism (i.e. the special gifts they have been granted by the Holy Spirit, cf. Romans 12:6; 1 Corinthians 12:11: “All these are empowered by one and the same Spirit, who apportions to each one individually as he wills”, for example within the family, in a charismatic group, in the Samaritan telephone service etc.), also with the expressed commissioning by the local church (pastoral assistant, pastoral counselling services etc.).
We differentiate between supporting and advisory pastoral care. Supporting pastoral care happens when the pastoral carer takes the initiative (e.g. home visits, visiting the sick), while in advisory pastoral care the initiative lies with the person requiring support: they seek help because of conflicts with other people or personal crises they cannot overcome on their own. (cf. Rolf Zerfass, art. „Seelsorge/Seelenführung“ [pastoral care, pastoral guidance”] in: Christian Schütz (Ed.), Praktisches Lexikon der Spiritualität. [practical lexicon of spiritualityI] Freiburg: Herder, 1988.)
So what does pastoral advice actually mean? The psychotherapist Lorenz Wachinger, who has many years of experience in pastoral counselling, writes: “It is [...] simply about a helpful conversation during the crises of life such as separations, goodbyes, the collapse of plans for ones life, ageing and dying. It is about a service offered to those who need it. [...] The core question is whether we are left alone in all our difficulties or whether there is community and support, whether there is a “church” in which we are not dismissed as sick or poor or simply “other”, but where a need is seen as a signal, also as a protest, as an opportunity of becoming more true to oneself. („Seelsorgliche Beratung“ [Pastoral counselling] in Walter Fürst & Jürgen Werbick (Hg.), Katholische Glaubensfibel. Rheinbach: Publishers CMZ-Verlag, 2004), p. 321-324.
Re (2): On how to deal with possession the Catechism of the Catholic Church says: When the Church asks publicly and authoritatively in the name of Jesus Christ that a person or object be protected against the power of the Evil One and withdrawn from his dominion, it is called exorcism. Jesus performed exorcisms (cf. Mark 1:25-26) and from him the Church has received the power and office of exorcizing (Mark 3:15; 6:7-13; 16,17). In a simple form, exorcism is performed at the celebration of Baptism. The solemn exorcism, called "a major exorcism," can be performed only by a priest and with the permission of the bishop. The priest must proceed with prudence, strictly observing the rules established by the Church. Exorcism is directed at the expulsion of demons or to the liberation from demonic possession through the spiritual authority which Jesus entrusted to his Church. Illness, especially psychological illness, is a very different matter; treating this is the concern of medical science. Therefore, before an exorcism is performed, it is important to ascertain that one is dealing with the presence of the Evil One, and not an illness.”