The Orthodox Church presents a view of sin distinct from views found in Roman Catholicism and in Protestantism, that sin is viewed primarily as a terminal spiritual sickness, rather than a state of guilt, a self-perpetuating illness which distorts the whole human being and energies, corrupts the Image of God inherent in those who bear the human nature, diminishes the divine likeness within them, disorients their understanding of the world as it truly is, and distracts a person from fulfilling his natural potential to become deified in communion with God.
Orthodoxy typically divides sin into two categories: Orthodoxy also understands sin as a disease of the soula condition where the soul is lacking in God's grace. Union with God, as made possible through Christis the ultimate Orthodoxy regards the mysteries of the Church, also known as sacraments in the West, as vehicles leading towards union with God.
From the Orthodox churches point of view, humans are not sexual creatures in terms of their essential identity. To Eastern Orthodoxy, the relationship which people have with God is reflected in the love for one another; the union of two people in marriage is considered to be a reflection of our ultimate union with God.
However, as a result of humanity's rebellion against God the Fallhumanity has tended to adopt a more animalistic view of sexual activity which is not true to the ultimate transfigurable nature of the human race, having been made in the Divine image "Orthodoxy and homosexuality in christianity" likeness.
Eastern Orthodoxy holds that Adam and Eve did not have sexual intercourse until after the Fall,  and that sexual sin and the Fall are intimately linked.
Reproduction must have happened in some way, however, for God commands Adam and Eve to "be fruitful and multiply" before the Fall as is stated in Genesis 1: The Orthodox churches do not hold that sex is inherently sinful, but rather condemn seeing sex as something which can be divorced from the loving act between a married couple.