In 119, the terms 'word', 'law' and 'statute' seem to be used similarly. I know some people
try to use Ps 119 to try to prove that the church must be brought under the law and that - never mind about Hebrews 7 - the church is institutionally a continuation of the synagogue. I myself do struggle with this way of reading the Psalms, though.
Blessings.
I think Heb 1:1-2 makes clear that the revelation spoken by the Son in these last days
through the NT writers, is the light in which the OT is to be understood.
Furthermore, the revelation spoken by the Son to
Paul, years after
the revelation spoken by the Son to the
apostles before his death and completed work,
is the light in which the gospels are to be understood.
And in this latter revelation of the Son through the NT writers in the
epistles, it is clear that
in the new covenant we are under the law of Christ (Mt 22:37-39; 1Co 9:21; Gal 6:2),
which is the law of love (Gal 5:6; Jas 2:8) that fulfills (performs) all the commandments
(Ro 13:8-10),
for the Mosaic law was set aside (Heb 7:18-19)
when God fulfilled Ps 110:4 by changing the priesthood in the order of Aaron
to the priesthood in the order of Melchizedek (Heb 7:11),
making Jesus the new and eternal High Priest of a new priestly order,
and changing the Mosaic law (Heb 7:12) which was based on the priesthood (Heb 7:11),
setting it aside (Heb 7:18) because it was weak and useless to make righteous (Heb 7:19),
and in setting aside the Mosaic law, God made the covenant based on it obsolete (Heb 8:13).
We are under a whole new order (Heb 9:10) in the new covenant,
where God's law is written
within, on our hearts, not on
external tablets of stone,
and where the Holy Spirit enables us to fulfill the law in loving the brethren (Ro 13:8, 9, 10).