Many people ask this question.
There are so many false churches out there. Yet many churches were called to teach. Sadly some have made light of the seriousness of keeping to the word of God.
Because of this, many churches today lack power and I’m not talking of miracles, healing, etc; this is good but the greatest power is upholding the word of God and sanctifying God through His word.
There is a very evil force out there, known as Satan’s power. It is a very great force that influences society and shapes it. It causes wars, hate, envy, malice, anger, murders, backbiting, cheating, corruption and just about every evil thing you can think of. It is a deadly force in that when it is finished with you it, will cause you to despise God and rebel against Him, leaving him no other alternative than to disown you and send you to hell.
The Church (the called out people) is the remedy against Satan’s power and his force.
The Bible says in Matthew 16:18-19.
 And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it.  And I will give unto thee the keys of the kingdom of heaven: and whatsoever thou shalt bind on earth shall be bound in heaven: and whatsoever thou shalt loose on earth shall be loosed in heaven.
You see, even though the gates of hell (forces of darkness) are powerful, they will never prevail against the church of God; why? Because the church can bind (stop) and loose (allow) things. What the church of God allows is allowed and what the church of God binds is bound. This is the power that God gave the church. That is why it is important to go to church, so that you can bind/loose things in yours and other people’s lives.
Another scripture in the Bible says:
 Behold, I give unto you power to tread on serpents and scorpions, and over all the power of the enemy: and nothing shall by any means hurt you.  Notwithstanding in this rejoice not, that the spirits are subject unto you; but rather rejoice, because your names are written in heaven.
Verse 19 teaches us the safety and comfort we have in being in a church (which is the body of Christ) or the body of anointing, protection, security. Verse 20 further strengthens and encourages us that our names are written in heaven as the people of God.
When you are grounded in a church, evil forces find it extremely difficult to destroy you. You become untouchable because of the great protection of God that you have. When you fall out of church and the teachings in church, you become isolated and vulnerable and because this you are exposed, you become an easy target for the devil (Satan). That is why it is important to go to church, so that you can be safe from the destructive aims of the Devil.
Hebrews 10: 24-25 shows us that we need to be in a church assembly (gathering) in order to stir each other up to do good. We should not forsake (abandon, reject or make little of) gathering together to praise and worship God and to learn about Him. When you come to church you think about others as well as yourself, building up others and helping them to ready themselves for the coming of the Lord.
 And let us consider one another to provoke unto love and to good works:  Not forsaking the assembling of ourselves together, as the manner of some is; but exhorting one another: and so much the more, as ye see the day approaching.
That is why it is important to go to church, so that you can help build others up as well as yourself, stirring others to come closer and closer to Christ. It is a command from God that we go to church for our own good.
“In church you will find people praising and worshipping Jesus, lifting up your spirit, encouraging, comforting, edifying and therefore building each other up in faith”
“In church you will receive teaching to eliminate bad teachings and habits from the past. You will learn the way of God and how to please him. You will be built and mightily strengthened to live a holy life unto God”
“In church you have a family who cares about you and will continue to pray for you until you are strong enough to support yourself and others. Your need is the need of the church, your joy is the joy of the church, your weeping is the weeping of the church (Romans 12:15).”
“In church you will be motivated, inspired, driven and empowered to do many things to the glory of Jesus. You will be equipped with the tools you need to achieve and God will use you greatly if you are obedient to him.”
“In church you receive healing, deliverance, soundness of mind and preservation.”