Don, thank you for your question. I wish we had this interaction before my book went to the publisher as your question illustrates one of the salient points of my book. One of my chapters is "The Precarious Nature of Prosperity Proof Texting"
The chapter synopsis says:
Where the prosperity gospel falters is that its development from the Scriptures is with utter disregard for any semblance of systematic, biblical theology. It fails to understand the Bible as a whole allowing the Bible to interpret the Bible. Jumping in and out of books, chapters, and verses, with utter disregard for context in the immediate with respect to the whole revelation of God to mankind, is the root of all aberrant beliefs in every age. What makes them so pernicious is that there is almost always a bit of truth contained within the "proof texts" giving them an air of plausibility.
Citing Joel 3:10 with your question is a perfect example. You cannot divorce Joel 3:10 from the context of the situation. namely God's judgment is promised to fall on the nations when they are gathered against God's people. This is a reference to the future days of the "End" but has relevance for the days of Joel as well. The statement you quote is expressly from God to His people related to the battle that is to come. when those nations gather against God's people, God will be the One fighting with them and for them. that changes everything! So in light of God's great promises for these coming battles, He--GOD--commands even the weaklings to be brave; with God for them, they will be strong and victory is assured.
Don--this is a far cry from simply tearing one verse out and using it as some kind of mantra. "Speaking it" over and over or even with great faith is not what makes it true; what makes it true is that God orders it with the specific application to the coming scenarios of Joel chapters 1 and 2.
Pastor Osteen no doubt means well--but is abusing the Scriptures'. He writes in chapter 1 of Your Best Life Now pg. 3 "We have to conceive it on the inside before we can ever receive it on the outside." "It" he goes on to define as anything your heart desires. In the context of his own words of chapter 1, he is referring to his dream home! He continues on pg 8. Referring to he and his wife's desire for this home he writes--"We kept believing it, seeing it, and speaking it."
The foundation of the New Age Movement was "you can create your own reality by envisioning what you want and bringing it into existence essentially through your will power since we are all wired into the "great divine" meaning we are all gods.
My friend, thank you again for allowing me to explain the destructive nature of today's "prosperity Gospel."