It is possible to be “in Christ” and be immature, not understanding fully what it means, not grasping the new possibilities and responsibilities set before us. The road to maturity is through teaching and instruction. What you need for that is teachers with boundless energy; and what you need for that is the life-giving power of the King Himself, working with Paul then and Christian teachers ever since. Great demands will be made on them. But the energy which Jesus inspires within them is always more than equal to the task.
Excerpt from Paul for Everyone – The Prison Letters by N.T. Wright