Luke 6:38 (New International Version)
Give, and it will be given to you. A good measure, pressed down, shaken together and running over, will be poured into your lap. For with the measure you use, it will be measured to you."
Sowing and Reaping is one of God's cardinal laws that will work in the spiritual realm, as well as the physical world. Just as we "give" seed into the ground to receive back multiple seeds, so it is with everything we give. Whether it's money, possessions, an emotion such as love or hate, prayers, or our time, we will reap a harvest of whatever we give. We reap exactly what we sow and proportional to the same measure that we give (Galatians. 6:7-8).
"He which soweth sparingly shall reap also sparingly; and he which soweth bountifully shall reap also bountifully" (2 Cor. 9:6).
This law works on positive or negative things that we sow. Although this is an unchangeable law of God, it can be overcome by a greater law in much the same way that we can escape the law of gravity by using the greater laws of thrust and lift. The negative things we have given don't have to come back to us if we apply the greater law of forgiveness (1 Jn. 1:9). Likewise, the good things we have sown can be voided if we don't continue in well doing (Galatians 6:9).
God is our source, but God uses people. If we pray for finances, God is not going to make counterfeit currency and put it into your wallet. He will use people to get the money to you. So, it is not always as simple as praying for money and receiving it the next minute. We need to believe the Lord hears and answers our prayers, and then pray for the people He's going to use to deliver the answer. This could mean any number of people such as our employer and the people who buy our goods. Ultimately God is your source, trust Him.
Genesis 1:28-31 (The Amplified Bible)
And God blessed them and said to them, Be fruitful, multiply, and fill the earth, and subdue it [using all its vast resources in the service of God and man]; and have dominion over the fish of the sea, the birds of the air, and over every living creature that moves upon the earth. And God said, See, I have given you every plant yielding seed that is on the face of all the land and every tree with seed in its fruit; you shall have them for food. And to all the animals on the earth and to every bird of the air and to everything that creeps on the ground—to everything in which there is the breath of life—I have given every green plant for food. And it was so. And God saw everything that He had made, and behold, it was very good (suitable, pleasant) and He approved it completely. And there was evening and there was morning, a sixth day.
Barry Bennett has received quite a revelation on the power of the SEED.