Article 139

The plaintiff and defendant, as the case may be, shall state in his pleading all matters which show the action or counter-claim not to be maintainable, or that the transaction is either void or voidable in point of law, and all such grounds of defense or reply, as the case may be, which, if not raised, would be likely to take the opposite party by surprise or would, without sufficient cause, raise issues of fact not arising out of the preceding pleadings.