Even the best among us are not absolutely reliable. We can change our minds. We can be caught off guard, grow tired, or run into other circumstances that might prevent us from keeping our promises. The same thing is not true of our Creator. He is the Rock whose promises cannot fail and who is fully and ultimately dependable. We can stake our very lives on His promises, for He will never, ever fail to keep them.
Take a moment to think about how you have changed over the years. Perhaps you are stronger or weaker today than you were ten years ago. Maybe you have progressed in your sanctification so that you repent quickly and love readily. Can it be that you have abandoned the lustful passions that characterized your pre-Christian life? Though we change in our abilities and characters, our Father does not. He alone provides a secure foundation for all of life.