Did you give someone a valentine card or gift?
Presents not only bring joy to the person receiving the gift, but also to the person giving the gift.
Knowing how much a friend may appreciate a written card or handmade picture frame, it brings me much joy to see them excited to receive a gift! Do you feel that way? How do you feel when you receive a gift? How do you feel when you see someone receive a gift you have given them?
So what does that mean for us? Does that mean that we don't ever have to serve God, or give offering to church, or help one another? No! God's delight is to see us worship and glorify Him in everything that we do. He also feels extreme joy when we give Him our daily gift of worship to Him. Now that doesn't mean that we should just recite a prayer so that God will be happy with us. It means that our hearts should reflect a desire to worship and surrender our whole lives to Him whenever we do pray or we do anything else!
So because God first loved us by giving us His Son as a gift to die on the cross so that we wouldn't have to experience eternal pain and suffering, we should also give God the biggest sacrifice that we can-- to live each day and each moment for Him and not for ourselves. This will bring the most perfect joy to both us and to God.