I remember there was a phase in our boyhood when my older brother would retort, "I sincerely doubt it," to almost anything I would try to state, frustratingly, as fact!
Have you ever wondered about the presence and purpose of doubt? Why do we get to have it and centipedes or toads apparently don't? Wouldn't life be easier if we could just get over it and move on?
Doubt plays an important function because it can save us from ourselves. Doubt can keep us from making bad decisions or doing harm due to run- away hubris, and thinking we're always right. Knowing we don't have all the answers is apart of honest humility. Faith without this kind of doubt can serve to strengthen, not question, all pet peeves and prejudices. Then, I no longer think I'm right, I know I am.
When it comes to the Bible, doubt means different things. One of the well-worn texts on doubt comes from the Epistle of James:
If any of you is lacking in wisdom, ask God, who gives to all generously and ungrudgingly, and it will be given you. But ask in faith, never doubting, for the one who doubts is like a wave of the sea, driven and tossed by the wind, for the doubter, being double-minded and unstable in every way, must not to expect to receive anything from the Lord. James 1:5-8
That's strong language against doubt. The gist of the doubt here is contention or differing with God. It makes sense. Why would anyone ask God for anything if they're going to turn around and say, "No thanks God, I changed my mind. I don't really want what you have to offer-wisdom- after all." So the doubter here is double-minded, or literally, "double-souled."
THUS, doubt depends on context. A truly healing confession is from Mark: [Jesus said] “Everything is possible for the one who believes.” Immediately the boy’s father exclaimed, “I do believe; help me overcome my unbelief!” Mark 9: 23-24
Doubt is about intention. Being careful for what you pray is only part of it. The other, maybe larger part, is about whether we choose the healed -or- sharply divided self. Doubt can play a helpful role if it can lead us to be more honest with God and genuine with other people. It can waste precious energy if we end up turning away from whatever God is offering us. It can lead to greater transparency or self-defeat. Choose the former, by God's love and grace.