St. Leo the Great (†461) says:
After the long feast of Pentecost, fasting is especially necessary to purify our thoughts and render us worthy to receive the Gifts of the Holy Spirit — Therefore, the salutary custom was established of fasting after the joyful days during which we celebrated the resurrection and ascension of our Lord, and the coming of the Holy Spirit.
A short while ago, we heard the words “Let us purify our sense that we may receive Christ”. Beloved this is not a once time event. There are some today who proclaim a belief known as “Once saved, always saved”, meaning the one time confession that Christ is your personal saviour is enough. Orthodox Christians recognize the perils in such a claim. We understand, as Yogi Berra would say, “it isn’t over until it’s over”. It is not until that fearful and most awesome day of Judgement that the books are finally closed and we are called to give account for our deeds in life. As such, our propensity for sin is great in this life. We must ever be mindful of our end, not in a way to crush us, but to carefully bring to remembrance our need for repentance.
We stumble along the paths of life and we know we must get back up with the hope, courage, and conviction that we will sin no more. Without this conviction of thought and will we will be convicted by our inaction.
Saint Leo the Great hearkens unto us to repent to worthily receive the gifts of the Holy Spirit. Gifts are given and may also be taken back, Our Father Job attests to this when he said: ” Naked came I out of my mother’s womb, and naked shall I return thither: the LORD gave, and the LORD hath taken away; blessed be the name of the LORD. Job 1:21 “. Let us also be wary to puff ourselves up in our pride thinking that we are so great, for we are naked before our Lord – there is nothing that we can conceal from Him.
Thus is our need for penitence. Indeed, we have passed the course of the Great Feasts of Pascha, Ascension, and Pentecost. Now we are charged to follow the path of the Apostles. They received the Holy Spirit and were sent forth to boldly go where no man had gone before – to spread the good news to the nations. This journey was filled with great peril but also incredible grace. So too are we called and sent forth. Therefore it is only meet that we should purify our senses and render glory as is due to the Holy Twelve and Seventy with Peter and Paul the foremost among them.
O foremost of the Apostles and teachers of the world, intercede with the Master of all that He grant peace to the world and great mercy to our souls.