One of the more common causes of doubt in one’s life can come in the form of a seemingly unchanged life, or as I like to call it, anecdotal proofs of a lack of growth. We look at our own sin, perhaps because we struggle with an addiction or perhaps we are introspective and get too critical of ourselves. Either way we look to ourselves or even to those close to us, if we think ourselves too holy, and we think, “Well, if I was a Christian, wouldn’t I be better than…this? Wouldn’t I be more Christ-like?” We see our own actions or lack thereof and we set that up as experience and proof that we must be unregenerate or at best a terrible Christian headed for unbelief.
To this I have two quick responses and encouragements. By its nature, our experience or view of our experience can be anecdotal, at best. It could never be proof on its own. The study population is too small, and the testing is too narrow. In other words, you cannot trust your own experiences as authoritative proof. Question your questioning, and doubt your doubts. If you do this fervently, you will find that the doubts hold less sway in your life. You are free to question and ask for proof, and sometimes you might get it.
A Second point to make is really just a reminder that we should tell ourselves often. It is a mantra we need to repeat to ourselves. If I worry about my salvation and sanctification, this is likely and evidence of my salvation. It might be too strong to try to call it a proof, but certainly an evidence. If I were unregenerate would I care about being more Christ-like? Would I care if my life showed genuine spiritual change? I would likely not. To be a Christian is to be intimate with doubt, and we can take comfort in that.
A slow pace or even perceived lack of sanctification is not an actual proof of unbelief. I do believe it was John Piper who said, when asked what his greatest source of doubt was, “the slow pace of my sanctification.”