By Rev. John S. Romanides (+2001).
Human beings can have two kinds of faith. The first kind of faith, which has its seat in the mind, is the reasonable faith of acceptance. In this case, a person rationally accepts something and believes in what he has accepted, but this faith does not justify him. When Holy Scripture says, man is saved by faith alone (Eph 2:8), it does not mean that he is saved merely by the faith of acceptance. There is, however, another kind of faith, the faith of the heart. It is referred to in this way because this kind of faith is not found in the human reason or intellect, but in the region of the heart. This faith of the heart is a gift of God that you will not receive unless God decides to grant it. It is also called inner faith, which is the kind of faith that the father of the young lunatic in the Gospel asked Christ to give him when he said, Lord, help my unbelief. (Mk 9:24). Naturally, the father already believed with his reason, but he did not have that deep inner faith that is a gift of God.
Inner faith is rooted in an (empirical) experience of grace. And since it is an experience of grace, what would this make inner faith as far as an Orthodox Christian is concerned? Inner faith is noetic prayer. When someone has noetic prayer in his heart, which means the prayer of the Holy Spirit in his heart, then he has inner faith. Through this kind of faith and by means of prayer, he beholds things that are invisible. When someone has this kind of vision, it is called theoria. Theoria, in fact, means vision.
As a rule, there are two ways for vision to take place.
When a person has not yet attained to theosis, it is still possible for him to see by means of the prayer that the Holy Spirit is saying within his heart. After attaining to theosis, however, he can see by means of theosis, in which both this inner faith (i.e., prayer of the heart) and hope are set aside, and only love for God remains (as a gift of God). This is what St. Paul means when he says: But when that which is perfect is come, then that which is in part shall be done away. (I Cor 13:10 & 13:13). Note that since faith and hope have fulfilled their purpose and man has reached the point of seeing God, the source of his faith and hope, he now simply knows and loves the One Who is Love.
When the perfect is come, faith and hope are thus done away, and only love remains. And this love is theosis. In theosis, knowledge comes to an end; prophecy is set aside; tongues, which are in noetic prayer, cease; and only love remains. St. Paul says this in passages of great clarity and beauty. The Church Fathers in turn offer interpretations of these subjects that are indisputably correct. These interpretations are found throughout the entire Philokolia.
Orthodox Heritage Vol. 10, Issue 05-04