Antonyms for "putting faith in" could include words such as mistrust, doubt, disbelief, skepticism, suspicion, and mistrust. These words all suggest a lack of confidence or trust in someone or something. When we are mistrustful, we are hesitant or cautious about believing in the reliability or sincerity of a person or situation. Doubt or disbelief implies a lack of certainty, even to the point of outright denial. Skepticism suggests a questioning or challenging attitude towards claims or ideas put forth by others. Ultimately, these antonyms all reflect a sense of wariness or trepidation when it comes to putting faith in anything or anyone.