Many people believe God's blessings work like a zero-sum game: if He blesses someone else, there's less for them. The speaker says that's a lie. When you rejoice in others' miracles, you're affirming that God's power is limitless and He doesn't need to take from one person to give to another.
Chapters
You see, it's one thing to rejoice with someone who receives their miracle. It's another thing to rejoice with someone who receives a miracle that's a lot like the miracle that you're believing for, because there's this scarcity mentality, something in human nature, this lie that we believe that says that if God gives it to them, he can't give it to me. Or if God does it for them, he can't do it for me. When actually it should be the opposite. Instead of becoming jealous, we should become inspired when God does it for others. We should say, if God gave it to them, he can give it to me. If he did it for them, he can do it for me. God is not running short on miracles. He doesn't have to take from you to give to someone else.