Old Adam's works are good because he says they're good. End of conversation.
Old Adam prefers not to talk about works that follow faith in Christ unless faith and works are things he can claim for himself. In fact, he'd prefer not to discuss Jesus at all, unless it has to do with the Son of God empowering or enabling him to get a pious leg up on everybody else. Faith talk, new life talk, forgiveness of sin talk is always another opportunity for old Adam to position himself in relation to God and neighbor as the center of attention. Any works old Adam does must be his own—measurable, comparable to others' works—works with price tags attached to them, otherwise how will he know his eternal status? That's why, ultimately, Old Adam could care less what God thinks of his works so long as he believes God is pleased with his works. Old Adam's works are good because he says they're good. End of conversation.
The flip side is, when old Adam hears about God's grace and mercy which just up and declares a sinner and his works "good" for Christ's sake, he turns up his nose in disgust. This is a wretched, desperate, and insane teaching. In the message of Jesus' all-sufficient work for sinners old Adam hears the end of his guilt-driven, fear-motivated reasons for doing anything for God and neighbor. More than that, the Gospel is the announcement that old Adam's works are useless, worthless, and advance him not one step toward the ecstasy of heavenly rewards.
The Good News of Jesus Christ which old Adam loathes is that all "good" works - that is, all true, godly works - are produced in and through a sinner by way of God's grace and mercy alone. Old Adam may prefer to judge his works in relation to laws, commands, statutes, by-laws, public opinion polls, and the 'yes' or 'no' of his personal taste buds, but regardless of how he judges his or his neighbor's works, they are wicked and incomplete because they don't come from faith. They don't come from God's fatherly hand. They are Christless, Spiritless works.
This then should drive old Adam to repent of all his good works, but it doesn't. Instead, he doubles down on works. He invents new works. He imagines more godly works for himself. He writes blogs and records podcasts that lay out point by point sure-fire methods anyone can follow to earn their way into God's good graces. Old Adam refuses to accept that true, godly good works always point to Jesus. All godly works point to what our Lord has done for us. Only then are works like a city set on a hill for everyone to see: Jesus, the Crucified, on Golgotha.
All God's works restrain Old Adam for the purpose of putting him to death. His end is Christ—the "It is finished" of his worthless, insane chasing after eternal rewards. True, godly works are always free gift from God’s fatherly hand, unchosen by us, fruits of the Spirit, productions of faith in Christ Jesus. God's works, like His grace and mercy, are always full and complete. But, so long as we're, "in the flesh" as St. Paul writes, God's works are hidden and obscured by our sinful, self-centered, me-first addiction to self-salvation.
You see, sin still clings to us even after baptism. Even after forgiveness, and renewal of life, and eternal salvation is declared to us as fact on account of Jesus Christ, our heavenly Father must continually reveal the truth to us. This side of the resurrection we are flesh—Old Adam who is doomed to fail at self-salvation, whose fate is death—and at the same time we are Christian, declared good, righteous and holy through faith in Christ (Rom 4:5). We are sinners whose every work, as sinful as it may be, is proclaimed as "good" by God for Christ's sake.
True, godly good works are not a divine program of self-improvement for Old Adam. They are the revelation of what Jesus has done, continues to do, and will always do in and through sinners on account of His grace and mercy. Therefore, when we talk about works, just like when we talk about faith or righteousness or salvation, we talk about Christ. No judging works or faith or ourselves according to Old Adam's measure of things. Instead, “Let the one who boasts, boast in the Lord” (1 Cor 1:31).
