You're not stopping the forces of darkness (sickness, fear, evil, lack) with your own strength—you're stopping them with the delegated authority given to you by God in Christ. You're backed by all the power of God.
Our life today is not too different from the times in which the Israelites lived, looking to God to fulfill their need despite their own perceived weakness and obvious lack.
We're talking about seeking God for His direction in every area of life: having answers, making the right decisions and being the most effective in everything we do.