The holy mystery of the day of the Holy Spirit, Pentecost, is to be understood in the following manner: the spirit of man must be completed and perfected by the Holy Spirit, that is, it must be sanctified, illuminated, and divinized by the Holy Spirit.
This holy mystery is realized continually in the Church of Christ and because of this the Church is really a continuous Pentecost…. From Holy Pentecost, the day of the Holy Spirit, every God-like soul in the Church of Christ is an incombustible bush which continuously burns and is inflamed with God and has a fiery tongue within it.
St. Justin Popovich, Orthodox Faith and Life in Christ