For the last several years, I’ve had the privilege and challenge of being on the teaching team for a second grade Sunday school class. Over the course of the last 15 years I’ve had the chance to be in a lot of rooms, lead a lot of discussions, and preach a lot of sermons, but this is one of the most intimidating. But it’s also one of the most encouraging.

It’s encouraging not only because of what we get to see happen in these children, but because of what I hear myself every single week. Every week, we talk to the kids about the promises of God, and about how we can trust Him to make good on what He says. We can take God at His Word because He always keeps His promises.

True enough, some of these promises are easier to accept than others, both for the children and for the teachers. But regardless of our opinions or feelings in the moment, they’re all true. Every last one of them.

Sounds simple, right? Believe in God’s promises? But it’s not. Maybe even more so for adults than children. There are certain things – ways of thinking – that can erode our confidence in God’s either ability or His willingness to keep His promises. What are those things? Well, the easy answer is circumstance. We encounter times of difficulty and trial and we think that those circumstances chip away at our resolve to believe. While that might be true, there are other things too that erode our confidence. And these things are not so easy to stomach, at least for me:

1. Our lack of scriptural grounding.

One of the most basic reasons our confidence in God’s promises erodes is that we simply don’t know them. Or at least we don’t know them as we should.

If we believe, for example, that “God helps those who help themselves” is a promise of God, then we’re wrong. God didn’t say that but Benjamin Franklin might have. That, of course, is an obvious example, but there are other ways in which we display our lack of scriptural grounding. We might down deep in our hearts still believe that we are on an exchange basis with God — that He’s going to reward us in this life with ease and prosperity when we give Him our acts of righteousness. Though less obvious, this too is an example of our lack of scriptural grounding.

In order to believe the promises of God, we must first know the promises of God. And we must know them well as they are, not as we would wish them to be.

2. Our own ambition.

Ambition can be a very good thing. We are to be ambitious in the things of God, “straining for what is ahead” (Phil. 3:13). But ambition can also be very selfish. That’s exactly what Paul warns against in Philippians 2:3-4. Ambition is one of those things that can erode our confidence in God’s promises. It happened to Moses.

You might remember that Moses had the right idea. He wanted the freedom of his people, the Israelites, from their bondage in Egypt. He was so passionate about it, in fact, that he killed an Egyptian and hid his body in the sand (Ex. 2:12). Right idea – wrong timing. Instead of trusting that God would deliver His people, using Moses as His instrument, in the right time, Moses took matters into his own hands. And we do the same thing all the time.

Discontent to trust and wait, we want to make “it” happen on our own. So we move, we act, we pursue – and though we might have the right idea and even some good intentions, we find all those efforts going nowhere. Our ambition has led us down the road of supplanting the work of God for our own. As a result, we might well find ourselves like Moses, hiding in a desert of doubt about whether or not God is actually true to His word.

3. Our short memories.

The Psalms were the songbook of the children of Israel. It was the tool of their worship, but it was also one of their tools for theological education. Through these songs, God’s people were reminded again and again of who God was for their ancestors and who He still was for them.

There is a near constant refrain through these songs – it’s the call to remember. Remember the Lord. Remember the Red Sea. Remember the great acts. Remember the past and be encouraged in the present. Sometimes our confidence in God’s promises wanes because we have incredibly short memories.

We fail to look back with gratitude on what God has done in the past – the way He has delivered us, provided for us, and shown Himself to be good and wise through all the particular twists and turns of our various stories. And of course we forget to look back to the cross – the ultimate and lasting demonstration of God’s love, wisdom, and trustworthiness. It was there, once and for all, that He let us know that He has and will keep His Word to us.

If you find today that your confidence in God’s promises is being chipped away, then, get in the Word. Read His promises. Check your ambition. Have you taken matters into your own hands? And then spend a little time thinking about who God has been for you in the past so that you can remind yourself of who He is… even now.