For it is with your heart that you believe and are justified, and it is with your mouth that you profess your faith and are saved."
-Romans 10:10
More than a mere organ, the Bible refers to "the heart" as what we would call our mind or consciousness.
Our behavior and conduct are measured by the effect our actions produce, and our actions are an expression of what is in our mind, serving as the ultimate seal or proof of our deepest convictions.
Scripture says both life and death, creation or destruction, are born in our "hearts" (Proverbs 4:23, Matt 15:19), meaning whatever effect or influence we have in our lives and the world around us is a product of what we decide to put into action.
These actions and decisions will come from what we're storing and treasuring in our minds (hearts), which will ultimately testify about what we truly believe in.
In other words, it's the walk you're walking, and how you are conducting yourself that will ultimately reflect what you truly believe in your heart (mind), and it is believing in Jesus' sacrifice within your heart that will justify in the end.
However, how selfish would it be to find a treasure so valuable & precious as eternal life and hoard it for ourselves without sharing it with others? Is it because of selfish ambition or shame of association, maybe?
Talking the talk without walking the walk might seem contradictory to others and create cognitive dissonance within us, but just walking the walk without talking the talk may also indicate altered motives and a weak belief rather than a deep level of conviction, leaving us vulnerable to inconsistency and hindering us from spreading and being associated with Christ and his kingdom, which should be our #1 priority.
Believing in your heart will reflect and show others Christ through you, but declaring him with your mouth will affirm his sovereignty over you.
