The Church measures time differently. Alongside the ordinary calendar runs the liturgical year, a cycle that begins not in January but in Advent and carries the worshiping community through the whole story of salvation — the waiting for the Messiah, his birth, his manifestation to the nations, his fasting and passion, his resurrection, his ascension, and the coming of the Spirit.
The year has two great poles. The Christmas cycle — Advent, Christmas/Nativity, and Epiphany — keeps the coming of God in the flesh. The Easter cycle — Lent, Holy Week, Easter/Pascha, and Pentecost — keeps the death and resurrection of the Lord. Between and around them lies what the West calls Ordinary Time and the East orders by the Sundays after Pentecost: the long season of growth and discipleship.
How fully the calendar is kept varies — richly in the Catholic, Orthodox, and Anglican traditions, more selectively in many Protestant churches, and hardly at all in some. But the instinct is ancient and shared: that the year itself can be catechesis, teaching the faith not in a lesson but in a rhythm, so that the people who keep it live, every twelve months, through the life of their Lord.