Do you ever have doubts about the sincerity of your devotion to Christ? If so, what do you pray and where do you go in God's word?
And the answer is, Yes, I do. And they're very scary. I don't blow them off.
I've been a Christian for 52-53 years. I've been in the ministry, I suppose, since I was 28 (before that, if you count seminary and school). And I'm 63 now. Why should I be wondering about this?
Satan is very, very deceptive. Our own hearts are very fallen. Indwelling sin is real. And there are low seasons in life that come from physical features, emotional features, and spiritual attack that make you ask the most frightening questions. "Am I doing this because I'm making a living at it? Am I a pastor because it has gone well (and why would you not want to have your life go well)? I haven't been persecuted enough recently, and I see some evidences that my life hasn't borne as much fruit as I would like." So, yes.
It is so scary when that happens because if that took hold and conquered, then you would be over. Your faith would be over, your ministry would be over, and it would be terrifying.
So I plead with the Lord to open my eyes. I plead with him to incline my heart to his testimonies. I plead with him to pour out the love of God into my heart. I plead with him to help me see the glory of Christ as self-authenticatingly real and compelling. And I go to those places in the Bible that speak of his subjectively-experienced and objectively-grounded love for me.
I'll just give you one. This is the way I did it this morning. I got up, and before I got out of bed, feeling some heaviness, I went in my head to Romans 5:5-6, because the two are brought together there: "Hope will not put you to shame, John Piper, because the love of God is poured out into your heart through the Holy Spirit who has been given to you."
So there it says that my hope will not put me to shame, because the experience of the love of God has been given to me by the Holy Spirit. And then it adds, "because (for) God shows his love to us in that while we were yet weak, Christ died for the ungodly."
That happened 2,000 years ago. I was loved 2,000 years ago, and now the Holy Spirit is given.
So where my mind goes is to the historic reality. He loved me there. Christ died for me. Holy Spirit, come! Open my eyes to this! Help me to see the wonder of this!
And he has to this point in my life. And I believe he will to the end. That's what the doctrine of perseverance is. To this point in my life, he has done it. He has done it, and I pray that he'll do it for you.