"I have been asked what I mean by "word of honor". I will tell you: Place me behind prison walls—walls of stone ever so high, ever so thick, reaching ever so far into the ground—there is a possibility that in some way or another I might be able to escape; but stand me on the floor and draw a chalk line around me and have me give my word of honor never to cross it. Can I get out of that circle? No, never! I'd die first." 

-Karl G. Maeser 

        What this means is that you always have to keep your word. If you make a promise you have to keep it. You can't make promises you can't keep. If you don't keep your promise people will start to believe you aren't trustworthy. For example, if you and your friend are doing a project. You promise to do one part and your partner another part. You are responsible for that part. You made a promise with the other person to do it. They are counting on you. The right thing to do is keep your promise.