miamited:" First, as regards the 'early' christians, we really don't have any evidence of how the very first gatherings used the time while they were gathered. We do know that they practiced communion, but as to whether or not they did any singing or giving of some sort of praise through song, we don't know."
On the contrary the NT provides abundant evidence that the early Christians sang hymns and songs during corporate worship: E. g.
Colossians 3:16: "Let the word of Christ richly dwell within you, with all wisdom teaching and admonishing one another
with psalms and hymns and spiritual songs, singing with thankfulness in your hearts to God."
Ephesians 5:19: "...speaking to one another
in psalms and hymns and spiritual songs, singing and making melody with your heart to the Lord."
1 Corinthians 14:26 "What is the outcome then, brethren? When you assemble,
each one has a psalm, has a teaching, has a revelation, has a tongue, has an interpretation Let all things be done for edification."
From corporate worship, Paul and Silas likely learned the hymns that they sang in the Philippian jail:
Acts 16:25: "But about midnight Paul and Silas were praying and
singing hymns of praise to God, and the prisoners were listening to them."
Indeed our earliest evidence for a high Christology comes from early Christian hymns quoted by Paul (e. g. Philippians 2:6-11; Colossians 1:15-20). Such texts are universally treated as early Christian hymns in modern NT scholarship. So the Odes of Solomon, the earliest serving Christian song book, reflects first century Chrisian hymnody and may well be traceable to 100 AD.
miamited: "Secondly, to base such things on 'how the Jews did it' doesn't really give us much help either. We all know that the Jews didn't then, and still don't, get it, for the most part."
You overlook the fact that in Palestine many first century Christians still attended Jewish synagogues and that the first Christians were Jews. Thus, the burden of proof rests with one who would claim that Jewish Christians would not adapt the elements of Jewish worship with which they were familiar (including singing and chanting) to Christian worship: and the OT is full of examples of Jewish songs sung during worship.
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