Dear Anthony:

Sorry for the delay in answering.

Once Churches began to be built (remember Christianity was illegal for 300 years. The earliest Churches in Rome were built with the asp and the alter so that the priest faced East. The Nave was also to the east side with the people facing West, so the priest faced the people. It just depended on the structure of the Church as to whether or not the priest faced the people.

Certainly, by the 8th century or so Churches were structured when everyone, the faithful and the priest, faced East (or liturgical East if the Church was not positioned literally to the East). Thus, the Priest faced the asp with his back to the people.

The imagery of the priest facing the altar with his back to the people is certainly, in my opinion, a richer symbolism, as it represents the priest as shepherd leading the flock toward their true homeland, but the priest facing the people can also have its symbolism.

 The significance of the east was well known to the early Christians. Like the rising sun, Christ (the Sun of Justice and Light of the world) rose in the early morning on the first Easter Sunday. The major prophet Ezechiel announces: "And behold the glory of the God of Israel came in by the way of the east ... And the majesty of the Lord went into the temple by the way of the gate that looked to the east. And the Spirit lifted me up and brought me into the inner court, and behold the house was filled with the glory of the Lord" (ch 43). St. Basil tells us: 

It is by reason of an unwritten tradition that we turn to the East to pray. But little do we know that we are thus seeking the ancient homeland, the Paradise that God planted in Eden toward the East.

Christianity was and is the only one to face East, to the New Jerusalem. Jews look toward Jerusalem, and Muslims look to Mecca

This is sort of like baptism. The preferred method of baptism in the Catholic Church is immersion, but pouring (the most common method today) is also valid. But, pouring lacks the richer symbolism of dying to self (immersed under water) and rising to new self in Christ (coming out of the water). Nevertheless, both methods are valid.

Whether the priest faces the people or not, it is still a valid liturgical form, albeit lacking in the richer symbolism.

Father Uwe Michael Lang stated about the phrase "with his back to the people":

That catchphrase often heard nowadays, that the priest "is turning his back on the people," misses the crucial point that the Mass is a common act of worship in which priest and people together — representing the pilgrim Church — reach out for the transcendent God.

What is at issue here is not the celebration "toward the people" or "away from the people," but rather the common direction of liturgical prayer. This is maintained whether or not the altar is literally facing east; in the West, many churches built since the 16th century are no longer "oriented" in the strict sense.

By facing the same direction as the faithful when he stands at the altar, the priest leads the people of God on their journey of faith. This movement toward the Lord has found sublime expression in the sanctuaries of many churches of the first millennium, where representations of the cross or of the glorified Christ illustrate the goal of the assembly's earthly pilgrimage.

Looking out for the Lord keeps the eschatological character of the Eucharist alive and reminds us that the celebration of the sacrament is a participation in the heavenly liturgy and a pledge of future glory in the presence of the living God.

This gives the Eucharist its greatness, saving the individual community from closing in upon itself and opening it toward the assembly of the angels and saints in the heavenly city.

It should be noted that Vatican II never mandated that priest must face the people. I think the current Roman Missale allows for either way.

P.S. It should also be noted that their is no such thing as a Novus Ordo Mass. The proper name for any Mass is "Roman Missal of _____ year". If nicknames are used then the appropriate nicknames are Tridentine Mass / Vatican II Mass, or "Pope Pius V Mass / Pope Paul VI Mass. Or, one might say the new Mass (in English), though it is no longer "new." But when use the Latin Novus Ordo, there is confusion because Latin is the official language in the Church and the official language of all titles. There is no official title of the Mass called Novus Ordo. In fact, the term was a term of derision by Ultra-Traditionalists. Unfortunately, it caught on. Nevertheless, the term is improper, misleading, and inaccurate.

God Bless,
Bro. Ignatius Mary