Since believers who not only live by the Spirit but also walk by the Spirit Gal 5:25; Ro 8:1,4 by walking by faith are not in the flesh, but are "in Christ" Ro 7:1-6, 8:9 (but those who had believed, but are not keeping the two commands whereby we remain in Christ 1 Jn 3:23,24, are not remaining in Christ--eg, the Galatians Gal 1:6, 5:4--the last Adam, Who became a life-giving spirit 1 Co 15:45, but are walking after the flesh, and will, unless there's repentance, die Ro 8:12,13, and not be supplied with the eternal life 1 Jn 3:24 that is only located IN God's Son 1 Jn 5:11), our walking in faith powered by love Gal 5:6 (fulfilling 1 Jn 3:23)
is not "work", because that is
Christ living in us, so that "activity"
cannot establish our righteousness Ro 10:3 (only activity proceeding from the flesh can establish our own righteousness, thus only that can be "work"), because walking in faith is categorically
not our righteousness, but it is God's righteousness 1 Co 15:10, revealed from faith to faith Ro 1:17, 14:5,23, for His own glory (do all you do to God's glory--but if
any activity at all is "work", then we could never glorify God, only ourselves, by proving we're righteous instead of proving God is righteous). We're in Christ, not in the flesh, so walking by faith is not "works", whereby our righteousness is established, but God's work whereby God's righteousness is established. Note: 1 Co 7 says whether a man lives the good life of the married man or the better life of the celibate man is his "gift", so "free gift of grace" is not nullified by the believer's walking in faith, but
describes their walking in faith.
Therefore, to say that one must walk by faith to be found in Him, not having a righteousness of one's own, and that that is how they attain to the upcoming resurrection of the righteous Php 3, is not incorrect--it's not "adding works", because the "works" that establish one's own righteousness flow from the flesh, not from God Who authors the persuasions Ro 14:14; Gal 5:8 of the Believer who not only lives by the Spirit but also walks by the Spirit.
This also explains why famous Protestant preachers (who shall remain unnamed) are so confused, and talk about how they have to "remind" themselves of the Gospel: they're relying on one single command of 1 Jn 3:23, but, then, they're sinning, and they're feeling condemned Ro 14:23, so they have to go convince themselves they're still right with God. If they obeyed BOTH commands, they would ALREADY have confidence before God. It's a complete mess--and I believe it's why they are all addicted to porn. "I'm still going to heaven!" No, all lawless will be thrown out of the Kingdom by the angels.