A proverb meaning that once suspicion takes hold, one begins to imagine all sorts of doubts and fears (suspicion begets monsters).
些細なミスを見つけると、疑心暗鬼を生ずことがあるから注意が必要だ。
If you find a trivial mistake, it can lead to suspicion begetting further doubts, so you need to be careful.
社内で不祥事が起きると、社員の間に疑心暗鬼を生ずことが多い。
When a scandal occurs within a company, it's common for suspicion to breed further distrust among employees.