The validation module provides an easy way to verify message content matches criteria. It has advantages over filters like providing traceability through customizable exception messages and types. Validators throw ValidationExceptions by default but allow customizing the exception and message. Validators can be used via message processors or MEL functions. Common validators validate fields like emails, sizes, numbers, and check for empty or null values. The All validator allows validating multiple conditions and returning a single error with all failure descriptions.