Substance in the Greek is hupostasis, which means "that which stands under" or the "real essence" of something. It means the very nature of something, that which is more real than its manifestation (check W.E. Vine's definition). In short, when a thing is in hupostasis form, it is more substantial i.e. has more substance than when it is in manifest form!!
Take healing, for example. Your healing exists in the glory realm. It cannot be tampered with or lost there. But you can lose your healing here. However, if you do, you can get it back anytime because it is in the glory realm! It's like those saints in Hebrews 10:34 who took joyfully the spoiling of their goods - they did so because they had in heaven a better and more enduring SUBSTANCE! They knew where they had got it and they knew how to get it back! Incidentally, the word "substance" used in Hebrews 10:34 is not hupostasis but it is a word that complements our understanding of hupostasis. It is huparxis and it means that which pre-exists. When you are healed here on earth it is because healing exists in the invisible realm.
The things you require here on earth exist already in another dimension - the glory realm. Your function here is to MANIFEST i.e. bring into the light these things. This means you are to bring them into the visible realm, where molecules are under the speed of light. Once you go past the speed of light you go into the invisible realm. All of reality is a spectrum. The speed of light is the point where the material, physical realm and the spiritual realm meet on the spectrum. God supplies all our needs according to the superabundance that is in the realm above the speed of light (Philippians 4:19).
Manifestation is simply the appearing of these things in the natural realm, the lower-than-lightspeed realm. Your part and mine is not to be a scientist and examine how God does this; it is simply to make sure we are full of substance (faith) so that it happens! It's not that the Lord doesn't reveal the how, it's just that you needn't know everything about it to use it. Millions of people who know nothing about the physics of electricity know how to boil their kettles, heat their homes and wash in their electric showers.
Your only toil under the New Covenant is to pack your inner man with substance. This means you cram God's Word into your heart by filling your mouth with it. The rest of faith is a rest of SUBSTANCE!! Once you have enough substance in you to fulfil your need or desire, you can sit back and let your faith (substance) manifest that need or desire for you. It is faith (substance) that does the job! Therefore, your only pressure is to make sure you are full of substance. Tank up on God's Word all the time to make sure you are full of substance.
Substance is heavenly materiality. When something is in faith form, it is actually more real than when it shows up in the physical. That is one reason why sometimes when we see our prayers answered in the physical it is actually quite matter of fact. Things in the glory are eternal; they are not subject to change as they are here in the natural. You can be robbed of a blessing here on earth but it is always there for you over there.
Receiving by faith is simply transferring the Word of God into our hearts. Take His Word and begin to speak it and you receive the answer to your prayer. Prayers aren't answered when the thing shows up in the natural dimension; they are answered when you receive substance from God's Word. That is why all His promises are yea and amen because all His promises are in His Word. God's promise is not "I will do it" - it is AMEN!!
It is done.
Fill up on substance today!