"Considero un pecado mortal no sólo mentir con los labios sino también no decir toda la verdad lo que implica engaño."

Simplified Meaning:

This quote means that being dishonest isn't just about telling obvious lies. It's also wrong when someone doesn't tell the full truth because this still tricks people. Think of a situation where a kid eats a cookie before dinner when they know they shouldn't. If their parent asks if they ate a cookie and the kid only says, “I didn’t eat *two* cookies,” they are technically not lying about the question asked, but they’re hiding the whole truth. This idea can be applied to many parts of life. For example, in a job setting, if an employee knows something important about a project and they don’t share it, they might cause problems for the team even though they didn’t directly lie. The advice here is to be honest and complete in what you communicate. Sharing the full truth builds trust and ensures that everyone has the right information to make good decisions.