Clearly, if there had been any instability in the first source of their teaching, there would also have been some disagreement in their preaching. But there was none in anything. Therefore the Christian teaching proclaimed by the Apostles, from the ever-faithful God the Father, concerning His never-changing Only-begotten Son, is an unchanging teaching. For this reason it deserves unquestioning acceptance, even though the Apostles were not always constant in the outward paths and plans of their activity. Finally, the highest testimony and visible proof of the indisputable truth of the faith received from the Apostles is every manifestation of God's grace revealed at conversion to Christianity. This was revealed through deliverance from sins in Baptism, and especially through the manifestation of various gifts of grace by the power of the mystery of Chrismation. In it a seal was, as it were, given. This seal confirmed the Christian union with God and filled the hearts of believers with gracious feelings. These feelings themselves speak of the truth better than any proofs or testimonies. Such proofs receive their force only from feelings that flow from the grace-filled anointing. According to Bishop Theophan's explanation, "The Apostle proves the unchanging faithfulness of his word by the very deed, by the very effect of preaching. We said: believe in the crucified Son of God and receive remission of sins. Through Baptism receive new life. Through the laying on of our hands be counted worthy of the gifts of the Holy Spirit, and this came to pass. The gift of the Spirit is God's seal in us. A seal on wax gives it form. The seal in our spirit is its formation through the action of the received Spirit of grace. Sealing by the Spirit is the giving of the Spirit into the hearts, or His indwelling in the inner man. This indwelling is a betrothal, that is, a pledge and earnest. It assures us that all the promises not yet fulfilled will certainly be fulfilled." Thus the Apostle gives full assurance not only of the truth of what was proclaimed, but also of the immutability of all the divine promises. Christians hope in these promises in the life to come.