Can we thank God for a doubt?

I know I didn't study about "doubt" enough to say anything, but anyway it is just an inspiration.
When you doubt someone, your conscience knows that you are not doing a right thing. Your conscience knows that you should trust people's good nature within no matter what kind of person he/she looks like. Especially when we know that person believes in the same God, then we should trust him/her more because he/she might have the same idea about what his/her good self would want to do and/or what it wouldn't want to do. If you cannot trust someone who share the same belief system, then how do you expect to trust someone who share a different belief system? At least, once you justify yourself to doubt someone even to its slightest degree, then it would immediately develop into further doubt and skepticism, which would persuade you to put on him/her many different "labels" which would further prevent you from seeing his/her good nature, and would build walls around you, which would make you not free in looking at and dealing with that person. Then you will find yourself treating him/her in a way which you would never want, but you wouldn't be able to control yourself any more because already certain power is produced beginning from that initial doubt as a seed. Therefore, when you allow yourself to justify your first doubt, then you may be selling your soul to the devil, of course without being aware of what you do.

Thus, doubting is so powerful. We have to at least be aware of this when we are in the situation which could tempt us to doubt someone. The battle is how I can keep myself to have a basic trust on people's good nature while many temptation comes to me to act otherwise. And of course, when you already doubt someone, it is still not too late. You just need to be aware of what's happening, and try not to benefit the devil any more. After all, the devil is the one that wants you to doubt people so that he could eventually claim all. People doubt other people and they hate other people, and they attack and kill other people. Then who becomes happy? No one becomes happy and the devil's claim just remains and only his purpose fulfilled.