God has a lot of choices. He can do a lot of things. Of all of the things He could do, He chose to do something for us. He chose to send His only Son so that we may be saved. Kind of a big deal. We also have a lot of choices. We can also do a lot of things (probably a lot fewer things than God can do). Of the few things we can do, since God did such a big thing for us, we should think about doing something for Him. And that something really isn't that big of a deal (difficult) for us to do but has a really big impact on our lives.
Lord, I believe in Jesus!