For the past two or so years I have tried my best to live by this scripture. Although I fail to follow it sometimes, or allot of times to be honest, I believe it to be one of the most important keys, for me, to be a positive light in this world. Psalm 19:14 "May the words of my mouth and the thoughts of my heart be pleasing to you, O LORD, my rock and my redeemer."
I have found that when my thoughts and words are pleasing to God, that its not God who benefits. Its me. Im filled with more peace and joy, and less stress and fear. Im able to grab hold of more of God's blessings for me, and avoid more of this worlds curses. Before we speak a word out of our mouth our brain must first process it as thought. So when I decide that Im not gonna speak negatively about something, my mind has think accordingly. When I change my words, I change my thoughts, and when I change my thoughts I change my heart. Jesus said "out of the abundance of the heart, the mouth speaks." So it stands to reason that if I just try to watch what I say, and be mindful of what Im thinking about, then I can literally change who I am where it matters most, the heart. And thats how I will be a positive light in this world, having a heart to please God.