The transitive verb believe and the phrasal verb believe in are similar but can have very different implications.
To “believe” someone or something means to accept specific pieces of information as truth: believe the news, believe the lead witness. To “believe a complete stranger” means to accept a stranger's story with little evidence.
To “believe in” someone or something means to hold confidence and trust in that person or concept: believe in liberty, believe in God. To “believe in one's fellow man” means to place trust and confidence in mankind.
Meanings sometimes overlap. To believe in a religious text would also require affirming the truth of at least the major tenets. To believe a religious text might likewise imply placing one's confidence and trust in it, in addition to accepting its statements as facts.
The translations below need to be checked and inserted above into the appropriate translation tables, removing any numbers. Numbers do not necessarily match those in definitions. See instructions at Help:How to check translations.