I don't see anything wrong with us following a local custom of beginning our education on Mahanavami day. If the Priest or the Church said that Mahanavami is more auspicious than other days and is the ONLY day to begin the education, then it is a different story.
Here are my reasons:
We all know that Christianity as a faith system we know today did not have age old culture of its own. The very first Christians were Jews; over time Gentiles also converted to Christianity.
The Church is the new Israel (The modern Zionist state that uses this name and follows the Rabbinic religion is not the new Israel). We the Church are the sons of Abraham; not those can claim genetic lineage from him. Our Lord clearly says in the Gospel :
"And do not think you can say to yourselves, 'We have Abraham as our father.' I tell you that out of these stones God can raise up children for Abraham." (Gospel of St. Matthew 3:9 also in Luke 3:8 )
The first Christians clearly understood this. Christians whether Jews or Gentiles are the NEW ISRAEL; and children o Abraham. So there was a debate about what the culture and tradition of this NEW ISRAEL should be ?
The Gentiles who primarily were Greeks or from a Hellenistic background had a very different culture from the Jews. The Gentiles ate any kind of food ; the Jews ate only kosher food. The Gentiles were not circumcised the Jews circumcised their new sons.
So there were two camps among the first disciples:
St. Paul and St. Barnabas argued that the Gentile Christians should be allowed to follow their own culture and traditions.
St. James the first Bishop of Jerusalem and some of the Pharisee converts to Christianity did not agree with St. Paul. They argued that thew NEW ISRAEL (ie the Church) should continue with the culture, traditions and laws o OLD ISRAEL.
It is interesting to see how the early church resolved this issue. It was not appealed to a Pope or Patriarch. For the entire Church , which was the body had only one head and that was Jesus Christ. So a Council (Synod) of Episcopas (elders) and leaders met in Jerusalem to resolve this. At this council the first among the Episcopas (elders) St. Peter addressed the council (synod) and council came up with a compromise:
From the entire law and traditions of OLD ISRAEL the NEW ISRAEL was just asked to abstain from food sacrificed to idols, from blood, from the meat of strangled animals and from sexual immorality.
You can read more about the Council of Jerusalem in Acts 15.
This is why we the NEW ISRAEL here in Malankara also does not follow the culture and traditions of OLD ISRAEL. With our faith in Jesus Christ; we are free to adopt our local culture. This is why in our Holy Sacrament of Matrimony we have 'thali' or 'minnu kettu' and the groom giving the bride the 'manthrakodi' or 'pudava'. These are local traditions that has been assimilated into a Sacramental service.
Similarly I don't see anything wrong with our faithful beginning their education on 'Mahanavami' day from a Priest in a Church. Now if the Priest said; Mahanavami is the ONLY day to being your education as it is a more auspicious day than other days; then it is problematic; because for us Christians every day is Holy as it is made by our Lord.
Mathew G M