What's potentially more harmful than lies is half truths.
They can be framed to look and sound like truths but they do more harm than outright lies because they aren't fully or even mostly true. They can deceive by appearing true and covering the falsehood they entail. They can convince the naiveté by highlighting and stressing only the true parts.
People who use half truths to sell their ideas are manipulative and cunning. They will use their words to bend reality. They will point out to you that if parts of it are true, the whole thing would be true. They will actively avoid probes and questions about the gaps in information. They wilfully cover up parts that are present in those half-truths and would break their arguments. They will oversell their moral high-ground and tell you to believe and trust them because they know better and you don't.
This, unfortunately, is also how most Christian leaders look like.