The structure of the Mass goes all the way back to the Apostles. There are two major parts: The Liturgy of the Word and The Liturgy of the Eucharist. Two minor parts act as book ends to the Mass: The Introductory Rites and the Concluding Rites.
We prepare ourselves to enter into the sacred mystery of the Most Holy Sacrifice of the Mass. These rites include the Procession, Sign of the Cross, Penitential Act, Kyrie, Gloria, and Collect.
THE LITURGY OF THE WORD
After the Collect we sit to meditate on a series of Biblical readings. Although the words we hear have been fixed in writing, we remember that they are the inspired Word of God and are truly alive (Heb 4:12). Through these readings, God intends to speak something new to us at this moment. We recall that the Word of God is not a book or a doctrine, it is a Person, Jesus Christ. These readings include a First Reading, typically from the Old Testament (except during Easter), the Responsorial Psalm, the Second Reading, which is always from the New Testament, and a passage from one of the four Gospels.
The homily is meant to explain or reveal the meaning within the Sacred Scriptures and how they apply to us today. Our response to the readings and the homily, is faith which is expressed on Sundays and Solemnities with the Creed. That faith is then used along with hope and charity as we intercede for ourselves and others in the Prayers of the Faithful.
The Introductory Rites and the Liturgy of the Word, prepare us for the climax found in the Liturgy of the Eucharist.
THE LITURGY OF THE EUCHARIST
Jesus’ sacrifice of Himself on the Cross is made present to us again by the priest who does what Jesus did at the Last Supper.
Within the Liturgy of the Eucharist there are many parts with many subparts. In the Preparation of the Gifts, the altar is prepared and the gifts of bread and wine are presented. These gifts represent the offering of our lives, so we should bring our joys, sorrows, successes, and struggles to the altar. While we desire to make ourselves into a perfect offering to the Father, we can never accomplish this task alone, but we can offer ourselves worthily in union with the perfect offering of Jesus on the Cross.
The Eucharistic Prayer begins with a dialogue. “The Lord be with you … and with your spirit…”and concludes with the Great Amen where the community expresses its assent of this prayer. Through this prayer, offered by the priest for the people, Christ becomes present. Simple bread and wine become the Body, Blood, Soul and Divinity of Jesus Christ. It is the highest prayer of the Church. As such, it is this part of the Mass that should have our greatest attention. The Eucharistic Prayer includes the Preface, the Sanctus, the Epiclesis, the Consecration, the Memorial Acclamation, Offering, Intercessions, Doxology, and the Great Amen.
We further prepare ourselves to receive Him in Holy Communion in the Communion Rite. This rite includes: The Lord’s Prayer, the Rite of Peace, the Agnus Dei (Lamb of God), and Holy Communion. Since we believe that Jesus is really and truly present in the Eucharist and not everyone shares that belief with us, we respect their beliefs by asking them to refrain from receiving Holy Communion because the very act of receiving communion means that the beliefs of the individual are the same as the community where they receive communion. In other words, to receive Holy Communion means that the person believes in all the teachings of the Catholic Church including the teaching that Jesus Christ is truly present in the Eucharist.
The priest greets the people, blesses them, and then the priest (or deacon) dismisses the people. At the end of Holy Mass, we give thanks and praise to Almighty God and we go out to bring this goodness to others through the conduct of holy lives.