Inasmuch as non-Christians do good, they are working with Christians in doing the will of the Lord Jesus. Non-Christian goodness does not supplant or negate the lordship of Christ. It confirms and demonstrates it.
God’s unconditional love does not imply that what we do doesn’t matter. Nor does believing that what we do matters imply that God’s love is conditional. The biblical truth is that God loves us unconditionally, and that is precisely why what we do matters.
Luke 2:14 has well known variant readings (is “good will” nominative or genitive?), and despite scholarship preferring one over the other, the choice between these readings is not clear. How do variant readings and translations affect our understanding of the inspiration of the Bible? What if ambiguities weren’t something God intended to work around but something he intended to work within.
Christmas is, or at least it should be, a season of joy. But what is the joy of Christmas? Joy is the natural human response to the good news of Jesus. This joy is the inheritance of every Christian.