do not conflate what is written in Romans 3:27 with what is written in Hebrews 8:10 ... that is improper interpretation of Scripture.
Here's what your good friend, John Gill, says about "the law of faith":
the word "law" here answers to the Hebrew word which signifies any "doctrine" or "instruction"
Other commentaries state that the "law of faith" should more aptly be rendered as the "principle of faith" as shown in the Amplified version:
Then what becomes of [our] boasting? It is excluded [entirely ruled out, banished]. On what principle? On [the principle of good] works? No, but on the principle of faith.
not only can a person reject ... Scripture makes clear that born again believers can improperly use what God has given.
In the church at Corinth, the believers were improperly utilizing the manifestation of the Spirit and Paul wrote 1 Corinthians 12, 13, and 14 to correct the misuse.
Ephesians 4:30 tells us
grieve not the holy Spirit of God ...
1 Thessalonians 5:19 warns us
quench not the Spirit ...
so, contrary to your stated belief, not only can a person reject God's grace ... but in addition, a person can improperly utilize what God has given.
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