I am reading a manuscript by Phillip King entitled The Bible is for Living, in which the following comment struck me—

“the New Testament is not necessarily a commentary on the Old
Testament, that is to say, Jesus is not to be found on every page of
the Old Testament. The Old Testament text is not simply shining
in reflected glory; it has rich meaning in its own right. Without
the Old Testament, the New Testament is a superstructure suspended
in midair. There is both continuity and discontinuity
between the Testaments. Jesus is the unifier of the Bible, both
Old Testament and New Testament; for example, the two great
commandments—love of God (Deuteronomy 6:5), and love of
neighbor (Leviticus 19:18). These two Old Testament injunctions
are combined in the New Testament: “You shall love the
Lord your God with all your heart, and with all your soul, and
with all your mind, and with all your strength … You shall love
your neighbor as yourself” (Mark 12:30-31; Matthew 22:37-39).” (p. 12 of mss.)

In what way are the two testaments united in and by Jesus, especially since the OT is not in the main about Jesus? One way would be to say that if we fulfill the Great Commandment(s) as Jesus said we should we would love Jesus with all our hearts as God and also love Jesus as our nearest neighbor (and so as our nearest and dearest human relative). A second way to look at this, is our modeling our love of God the Father and neighbor as Jesus himself practiced it, showing us the way.

Think on these things.