Imam Sadiq (a.s) quoted the following from Prophet David (a.s): “O' God! One who does not have a good opinion about You has no faith in You even if he has gotten to know you.”
عنه (عليه السلام) قال
قال النبي داود (عليه السلام): يا رب ما آمن بك من عرفك فلم يحسن الظن بك.