Psalm 89: 34
My covenant I will not violate, nor will I alter the utterance of My lips.
We have a covenant with God and He has made us promises. He has sworn on Himself, because there in nothing higher, holier or more sacred for Him to swear on, that He will not violate His promises to us. He cannot and will not alter one syllable that has ever come from His lips. If He has said it, He will make it so. You can bet on it. Imagine, if you will, someone who is completely incapable of lying. That is God. He lacks the ability to lie. Whatever He says becomes reality. It is truth. Therefore, whatever promises you find in our covenant, you can depend on them 100% because He has told you in this verse that He will not change one thing that He has said. Furthermore, you are invited by God to remind Him of His promises. He likes for you to have that level of confidence in Him that you are willing to hold His promise up to Him and claim it as your own.
You can have absolute confidence in the Word of God because it is the unalterable truth of the living God. Get out your Bible and dig around in there. Any promise you find, any utterance of God is yours for today because He cannot and will not change. All of the Old Testament promises are yours because the Old Covenant has been fulfilled in Jesus. All of the New Testament revelation is yours because Jesus established the new covenant in His blood. Any promise of God is yours for the taking. Fill your shopping cart with His promises.