Have right belief ("ortho-doxy") and good works! Whoever has these two has certain hope of eternal salvation. As Scripture says: "You see then that a man is justified by works, and not by faith alone." (James 2:24) A little later in the same place: "For as the body without the spirit is dead, so faith without works is dead" (James 2:26). Elsewhere St. Paul says the same thing: "…having faith and a good conscience, which some have rejected, concerning the faith have suffered shipwreck" (1 Tim. 1: 19).
 

The early Church called the Sacraments of the Church, Holy Mysteries. Mystery is the reality through which the invisible grace of God is effected in or conferred upon the souls of the faithful under a perceptible form (sanctified matter). It was established by Christ as the means through which the faithful appropriate the grace of God.

To provide remedies for removing our sins.

Seven: Baptism. Anointing with Chrism. The Holy Eucharist. Ordination. Penance-confession. Holy Matrimony. Healing consecration with oil.
 

When the young Church was getting underway, God poured out His Holy Spirit on the Apostles and their followers, giving them spiritual gifts to build up the Church and to serve each other. Among the specific gifts of the Spirit mentioned in the New Testament are apostleship, prophecy, evangelism, pastoring, teaching, healing, helps, administrations, knowledge, wisdom, tongues, and interpretation of tongues. These and other spiritual gifts are recognized in the Orthodox Church. The need for them varies with the times. The gifts of the Spirit are most evident in the liturgical and sacramental life of the Church.
 

Saint Irenaeus said where the Spirit of God is, there is the Church. We believe there is only one earthly Church (“I believe in one, holy, catholic and apostolic church” – the Nicene Creed). We know where the visible Church is, but we cannot know for assurance where the Spirit of God may or may not be outside ‘the one, holy, catholic and apostolic church’! Orthodox Christians must not therefore presume to pass judgment on non-Orthodox Christians or their communities, think or speak triumphalisticaly about the Orthodox Church, but rather strive to live out their faith without compromise, in humility and repentance.
 

Free will is man's unrestricted ability to decide from reason, which leads to doing good and evil. This reason was complete in its perfection during the state of man's innocence (before the Fall), but  became damaged on account of sin. However, although the will remained inclined to evil (after the Fall) it is still nevertheless able to choose to do good. St. Basil the Great: "From one's intention and free will anyone can be holy or the opposite.” And in the Gospel of St John: “’But as many as received Him, to them He gave the right to become children of God…."' (John 1:12). If this were not the case (use of free will) it would not be possible for St Paul to write of “the righteous judgment of God, who ‘will render to each one according to his deeds.’” (Rom. 2: 5-6). How could we be judged by God by according to our deeds if our will is incapable of choosing between good and evil?
 

Orthodox Christianity and the early Church teaches that the Lord will come once and for all after the tribulation (Matthew 24: 29 - 31). The Nicene Creed states that Jesus Christ, ‘will come again with glory to judge the living and the dead, whose kingdom shall have no end’.  On that day everyone will receive eternal and perfect payment for their deeds. There is no-pre-tribulation “rapture", nor is there a  one thousand year reign taught in the Holy Scriptures, or by any church father east or west. In fact, the 5th Ecumenical Council of the Universal Church specifically rejected the idea of a "thousand year reign" as a heresy! These heterodox teachings supposedly came through a dream someone had in the 18TH century and were subsequently promulgated by the Scofield Bible translators and adopted by certain Protestant Evangelical groups later.
 

No Scripture makes mention of a temporal punishment that cleanses souls after death. In fact, the opinion of Origen was condemned because of this by the Church at the Second Council of Constantinople. The soul can receive no sacraments after death; and if it were to make satisfaction for its sins, it would have to perform a part of the sacrament of holy Penance, which would be contrary to the orthodox teaching.
 

Out of love for them! Orthodox believe from the teaching of Sacred Scripture that we are obliged to pray to God for the departed, to offer the Holy Eucharist for them in remembrance and to give alms in their behalf, since they cannot do this for themselves. We leave the results – or even whether there is efficacy in prayer for the departed, since we cannot know for certain – up to God and His mercy.

Blessed Theophylact speaks about this: "For the sinners who die are not cast into hell (until the Final Judgment); but it rests in the power of God such that he may even pardon them. But I say this because of the sacrifices and almsgivings made for the sake of the dead, which works are of no small benefit even for those who have died in grave sins. It is not so certain, therefore, that God sends to hell one who has killed, but rather that he does have the power to send him. And so let us not cease working hard through almsgiving and prayers to win over him, who has indeed the power of sending, so that he may not use this power fully but be able to pardon.”