The Wedding of Overlord Zim and his Love-Pig

"Before we get on to the next person, I would like to say a few words" Dib clears his voice and started his speech, "There's an Irken saying, or so I've been told. An enemy will point a knife to my back, but an Ally shows his blade to my face. What does that mean? Well, I didn't understand it as well at first until my fiance help clarify it for me." (Clarification - ZAGR and DATR)