God has provided us with some powerful weapons that He has given to use to use against the devil, sickness, and problems. The main 3 weapons He has blessed us with is The Word of God, The Name of Jesus, and The Holy Spirit. As in Hebrews 4:12 "The word of God is quick and powerful." In other words the word of God is capable of performing exactly what it says. In Isaiah 55:11 it says God's word will not return to him void, but it will accomplish that which He pleases. Notice it says it shall accomplish, it(the word of God) will accomplish. But let's go a little further, how will it accomplish by being spoken. Notice it says "My word shall not return unto me void, but it shall accomplish that which I please. Well for his word to be returned to him someone has to speak it. But here's where a lot of people miss it, it's not just the word spoken but the word believed and spoken. Jesus said, "For verily I say unto you that whosoever shall say unto this mountain be thou removed and be thou cast into the sea and shall not doubt in his heart but shall believe that those things which he saith shall come to pass he shall have whatsoever he saith." God has blessed and honored us with the privilege to release his power out of our mouth "For I am not ashamed of the gospel of Christ for it is the power of God unto salvation."
Another weapon is the Name of Jesus, the name of Jesus is not just a name it is a representation of the person. In other words even though Jesus is in Heaven He left us his name to do his business in the earth. Even though Jesus is in Heaven his name is just as he is. Jesus is far above all principality and power and might and dominion, and every name that is named (Ephesians 1:21) and so is his name God has given him a name which is above every name (Philippians 2:9). When Jesus walked the earth devils bowed to him and now the bow at his name (Philippians 2:10). When Jesus walked the earth He healed the sick and his name does now. Notice Acts 3 the lame man was healed because they had faith in the power of the name of Jesus. In verse 16 Peter said it was faith in the name of Jesus that healed the man. When Jesus walked the earth He did great sign and wonders and his name does them now. In Acts 4:30 notice they prayed that signs and wonders would be done by the name of Jesus. There's no other name under heaven given among men by which we must be saved (Acts 4:12).
And the Holy Spirit is another weapon, when Jesus was baptized the Holy Spirit came upon him, but not just the Holy Spirit but power. Power always follows the Holy Spirit. Acts 1:8 says "But you shall receive power when the Holy Spirit comes upon you." And Acts 10:38 says "How God anointed Jesus of Nazareth with the Holy Spirit and with power." The same Holy Spirit Jesus had when He walked the earth is the same Holy Spirit we receive. And when faith and the Holy Spirit comes together power goes to work. In Act 6:5 it says Stephen was full of faith and the Holy Spirit then 3 verses later it says Stephen was full of faith and power. And with faith and The Holy Spirit(power) great signs and wonders were performed. Remember wherever The Holy Spirit is power is there.