"People do not drift toward holiness. Apart from grace-driven effort, people do not gravitate toward holiness, prayer, obedience to Scripture, faith and delight in the Lord. We drift toward compromise and call it tolerance; we drift toward disobedience and call it freedom; we drift toward superstition and call it faith. We cherish the indiscipline of lost self-control and call it relaxation; we slouch toward prayerlessness and delude ourselves into thinking we have escaped legalism; we slide toward godlessness and convince ourselves we have been liberated." -D.A. Carson-
In this quote, I think Carson touches on a very important trend I've noticed within myself, and also among Christians in general. The trend is this: Grace and disciplined effort are opposed to each other. I'm afraid we have created a dichotomy between resting in God's grace and grace-driven effort as if the two are mutually exclusive. Unfortunately, a lot of times I find myself drifting into this mentality that mistakes laziness with true gospel rest.
Yes, the gospel does save us from having to justify ourselves with our own works and from having to prove our selves day in and day out. However, it also saves us to something. It frees us from the slavery of sin and of self-justification and, in turn, frees us to pursue righteousness. The gospel frees us to life as it was meant to be lived.
In Christ, we are no longer slaves to drift into compromise, disobedience, and lifelessness. In Christ, we are free to drift towards God. We are free to experience his grace in such a way that we are driven to action. God's grace is the empowering force behind our discipline and it is our motivation. With that being said, diving deeper into in the gospel and the union we have with Christ necessarily results in actively sharing in this life.
Further, as Carson points out, our default gravitation is not towards holiness. Our default mode is to sink deeper and deeper into self-worship. Therefore, we must run to the gospel everyday and look to God's grace as the source of our effort in order to live this life. It is a mistake to call this legalism or unnecessary effort. God longs for his children to live in him. He longs for his children to experience the power of his resurrection. He longs for his children to freely obey him. We only find this in the gospel of God's grace. When we taste of this, only then will we be in hot pursuit of righteousness.