The dread Mysteries, full of such great salvation, which are celebrated at every Liturgy, are also called a Thanksgiving [Eucharistia] because they are the remembrance of many benefits, and they signify the culmination of God's Providence towards us, and in every way cause us to be thankful to Him.
But if you are fearful of becoming self-righteous from working for your own salvation, or afraid of being overcome by spiritual pride, examine yourself and observe that the person who is afraid of becoming self-righteous suffers from blindness. For he does not see how self-righteous he is.