"Man looks at the outward appearance, but the Lord looks at the heart" (1 Sam 16:7)
How many times have we said or heard others say "God knows my heart."? It's our defense for pretty much anything that makes us look bad. You know, our way of saying, "oh I know this doesn't look good, but God understands where I'm coming from...right?"
In Matthew 6, Jesus talks a lot about image vs lifestyle. The three areas that he mentioned were giving to the needy, prayer and fasting. Jesus warns the crowd about the public displays that had been associated with those things. That wasn't what giving to the needy or praying or fasting was all about. This passage is a gentle reminder that our motives behind our actions shouldn't be the glory or recognition that we receive from others for what we have done, but rather the glory we will receive from God, who sees both our actions and our intentions. That is to say, our actions should be motivated by our pursuit of a God-like lifestyle, and not by a desire to portray a God-like image.
Our motivations should not be to do things so that others can see what we're doing and say "My, what a good person X is!" Rather, we should do them because we see a need that needs to be met, or from a desire to serve God and others, or to further our relationship with God. Because while people only see the outer appearance of your actions, God is taking careful note of the place that your heart is in. This is what he cares about. The earthly glory fades, but if what you treasure is stored in heaven....well that's eternal.
Be blessed and shine intentionally!