Likewise, more specifically, could I use Old Testament ordinances and scriptures to support liturgical worship against contemporary modernist worship?
Why do such a thing? Why not focus on the cathecumenate because to answer your question - the New Testament, in Jesus Christ, fulfills the Old Testament. What happened in the Old Testament was supposed to prepare the children of Israel for the Messiah. When the Messiah came, he was crucified (even that was prophecized in the Old Testament).
I don't know if JamesR could say that without defining contemporary modernist worship.
For instance, Messianic Jews worship in Aramayic and on the Sabbath. This practice many early Christians did.
Some may consider the Liturgy of St. John Chrysostom modernist compared to the Liturgy of St. James
Then you could go into the "modernist" new calendar.
Or the old believer Orthodox would call the current mainstream EO church modernist...
Modernist can be defined differently.