It's important to keep promises, especially the ones you make to yourself. You either build yourself up by being trustworthy or you tear yourself down by not being so. You can fool other people. You can make it look like you did a bang up job when you know you cut more corners than a poorly trained carpenter. You can over-commit and look like the person who does it all for everyone. But YOU know if you keep your promises. You know when you don't.
We don't tend to like people who fail time after time to keep promises. Failing ourselves leads to self-hate. And if we are hating ourselves, we cannot love God. How, if we are filled with self-loathing and hatred, can we fulfill the greatest commandments? (So you don't have to look it up: Mt. 22:37-40 he said to him, "you shall love the Lord, your God, with all your heart, with all your soul, and with all your mind. This is the greatest and the first commandment. The second is like it: You shall love your neighbor as yourself. The whole law and the prophets depend on these two commandments.") Someone who is full of hate cannot truly love and someone full of self-hatred cannot love their neighbor. There's also that pesky business of what we do to the least of our brethren (aka neighbors), we've done unto Jesus. If you are so small, dare I say "the least," and you hate yourself, have you not hated Jesus Himself?
Something to ponder today. What will you promise yourself today. Make it something small and something that you WILL do. Will you get up on time for a week instead of hitting the snooze button? Will you plan and cook one week's worth of dinners? Will you read just one story to your kids every day for two weeks, no matter how busy you seem to be? Will you grade just one paper every day for a week? Will you open every piece of mail that comes in your house today? It doesn't have to be "organize a new food pantry for the homeless" huge... it just needs to be something you promise and deliver to yourself. If you do that, you've done it for Jesus.