Unrestrained lips

I have proclaimed the good news of righteousness In the great assembly; Indeed, I do not restrain my lips, O LORD, You Yourself know. - Psalm 40v9

While sometimes the Bible speaks of keeping our mouths shut, it can also speak sometimes of the importance of speaking out. My problem tends to be that I get it backwards. I talk about the things I should not talk about and I don't talk about the things that I should.

While we are supposed to have muzzled lips when it comes to evil speech, the psalmist here speaks of having having unrestrained lips when it comes to speaking of the goodness and righteousness of the Lord.

I know that it is much easier for me to gossip than it is to praise. I know that I have a much easier time defending myself than defending my Lord.

Why is it that people like me have no problem expressing our views on sports or politics or the news or almost any other topic, but such a hard time talking about our Lord?

That really bothers me. If we indeed talk about the things that are most important to us, and speak so much more about things that relate to me than things that relate to the Lord, what does that say about how important He really is to me?