Luther on Your Doubt Peddlings

We are better equipped to doubt than to hope; because hope comes from the Spirit of God but doubt comes from our own spirit. Accordingly God has forbidden it [doubt] under severe penalty. That we more easily believe penalty than reward is a product of the reason or spirit of man. Hoping and believing are different from thinking and speculating. Reason sees death before it, and it’s impossible for reason not to be terrified by it. Likewise we can’t be persuaded [by our reason] that God gives his Son and loves us so much, and hence we say, ‘You have not allowed your Son to be crucified for nothing!’ This is above reason. That God is so merciful, not on account of my works but on account of his Son, is incomprehensible. –  Martin Luther