Since being productive is ultimately about love, it therefore follows that time management is actually a component of our sanctification. This seems to be what Paul is getting at in Ephesians 5:15-17 (the core NT passage on time management), and that’s ultimately the reason for the name “What’s Best Next.” In this passage, Paul commands us to “make the best use of the time” and he shows that this doesn’t come from following a bunch of rules, but from walking as “wise” people who “understand what the will of the Lord is.”
God doesn’t drop his will down from heaven directly to us, whispering in our ear what decision to make in every situation. We have to make decisions, prayerfully, based upon biblical principles. And there is usually a lot of freedom in the specifics. But the freedom of the Christian is a structured freedom, rooted in God’s truth and character. Hence, what we choose is an expression of character. The choices we make reveal something about us and shape us, and thus are an outworking of our sanctification.
This is also why character is at the root of true productivity, not techniques and tools (as cool and important as they are). For, as Paul conceives it, character is the source of our ability to make good decisions (i.e. to know and do what’s best next).
See also Philippians 1:9-10 and Colossians 1:9-11, where Paul roots our ability to make good decisions not just in wisdom but also in love.