Unless you are willing to put some CONTEXT where such a statement is applied, then such a thing is rather meaningless. Don't be surprised if you end up with replied that have nothing to do with what you are thinking of.
Here is one simplistic non mathematical attempt to answer:
Suppose while I stand on the Earth I am a "loaded structure" gravitationally with the earth, we both attract each other with equal force. The Earth and I are in our ultimate equilbrium and stable state with respect to each other as a "loaded structure", thus our potential gravitational bond energy P = 0. I now transform the system and I walk up one unit of distance away from ultimate equilbrium state with the earth. Potential gravitational bond energy for the system has now increased to P = +1. Next, I step back down one unit of distance. During the process of stepping down I gain kenetic energy and lose potential gravitational bond energy, I return to P =0 state. Thus, the potential bond energy (P) of the loaded system (me & earth) is minimum (=0) at our ultimate stable equilbrium state.