It is the same with the law of sowing and reaping. Some people have sown seeds of hate all their lives. Some people have sown seeds of love all their lives. Some ministers are always criticizing others. You will reap what you sow.
Every law has two ends, a positive end and a negative end.
You can use electricity to cook your food and heat your home, but if you violate the law that governs electricity then it can also kill you. The law of sowing and reaping can either work for you or against you. For instance, if you sow money seeds into God's Kingdom then you will reap money. Not immediately, but the Word says that in due season you shall reap, if you faint not. Think about it and ask God to help you sow good seeds, not bad seeds.