In high school football I was taught to watch the ball carriers waist. The arms, legs, and head could play tricks on me. The ability of a running backs waist faking me out was close to non existence. The waist is the core of the body and where it is headed the ball was going. I think in the same way here Paul is encouraging us to infuse in to the core of who we are as Christ followers. The truth of Gods Word. May what the Word says guide our thoughts and actions. The belt of truth not only holds our pants up, but it tells us who we are at the core of ourselves.
In the same way the breast plate of guards our hearts and communicates to the world who we are. I sometimes forget that this is what I have on. The breast plate is not meant to bring judgement into my relationships. It is designed to show people around me that I stand for what is right in this world and the rightness is Jesus. That they may come to me and discover Jesus.
Lord I pray that I never get comfortable in the armor of God. That I be grounded in your truth and bring your righteous love into every moment of my day. Not to be right but to make right every wrong in the world. I love you and I want my life to say that.