Hebrews 11:1 Now faith is the substance of things hoped for, the evidence of things not seen
Believing is making the heart shift that goes from hope (knowing that something is available to you) to faith (believing that it is already yours). Faith obtains things in the Spirit before the natural is changed.
This is why you can’t consult the natural when you are believing a promise. You must only look at the Word of God and believe what it says without rehearsing the problem. Believing produces faith which is called a “substance” in Hebrews 11:1.
When you have this “substance” in the Spirit and you do not waiver, you WILL have it in the natural. Many fail in faith because they never acquire the “substance” with their heart. No Spirit “substance” means no natural change.
You will not acquire the “substance” in the Spirit without a whole-hearted life-and-death taking hold of the promise until you “have it”. But you will have it EVERY TIME if you gain the “substance” AND HOLD IT until the natural changes.
This is not done mentally. This is done with an undivided and whole heart which “feels” like HYPER-FOCUS ON A GOAL TO BE ACHIEVED.