The difference between Galatians 3:10-11 and Philippians 3:6 is subtle although they are similar in the fact that they both are based on man made beliefs. In Philppians 3:6, Paul is saying he was perfect in the Pharisee's traditions according to their laws. This would include in part some of God's Old Testament laws and their own man made traditions. Galatians 3:10-11 is speaking of the Law as a package deal in how it is no longer in effect anymore because it was a part of the Old Covenant. These were laws of God that were in effect at one time as a whole or package deal until Christ died upon the cross and instituted the New Covenant with New Commands for us to follow after we received his free gift of grace. Yes, the Pharisees decided to come up with the man made idea of saying that man is justified by a Covenant Law that is no longer binding without a Savior, but that is not the same thing as keeping their man made traditions that was an addition to God's Laws in Philippians 3:6. For Matthew 15:1-2 says,
"Then the scribes and Pharisees who were from Jerusalem came to Jesus saying, 'Why do Your disciples transgress the tradition of the elders? For they do not wash their hands when they eat bread'".
What did Jesus do?
Jesus had a problem with the Pharisees's Traditions:
"He answered and said to them, 'Why do you also transgress the commandment of God because of your tradition? For God commanded saying, 'Honor your father and your mother'; and he who curses father or mother, let him be put to death.' But you say, 'Whoever says to his father or mother, 'Whatever profit you might have received from me is a gift to God'--then he need not honor his father or mother.' Thus you have made the commandment of God of no effect by your tradition. Hypocrites! Well did Isaiah prophecy about you, saying: 'There people draw near to Me with their mouth, and honor Me with their lips, but their heart is far from Me. And in vain they worship Me, teaching as doctrines of God the commandments of men" (Matthew 15:3-9).
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