What is a true worshiper? We know from Jesus' words to the Samaritan woman at the well that a true worshiper is one who worships the Lord in Spirit and in truth. But there is another mark of a true worshiper, and it can be found in Genesis, chapter 22.
Abraham was commanded by God to take his son, Isaac, to the land of Moriah and offer him as a burnt offering. Isaac was the son that God had promised Abraham. He was born to Abraham's wife, Sarah, in her old age, despite the fact that Sarah had been barren all her life. So, to Abraham, Isaac was precious. And yet, Abraham took Isaac and headed off to sacrifice him to God. (Genesis 9:1-8) When they got to the place where God had told Abraham to offer his son, Abraham didn't hesitate. He built an altar, bound Isaac and laid him on it, then reached out his hand with a knife to sacrifice his son.
Abraham is an example of a true worshiper. A true worshiper does not hold back anything from God but, in obedience to Him, is willing to give God all that He requires and all that He deserves (Romans 12:1). Like Abraham, we are called to be true worshipers. God may not require us to sacrifice our children, but He does require that we give our lives completely to Him. We should hold nothing back from God. More than anything, God wants our obedience (1 Samuel 15:22).
When we worship God through our obedience to His commands, when we hold nothing back from Him but give Him our all, God is pleased with our worship. Abraham was willing to give his son as his act of worship but, when he lifted the knife to perform the sacrifice, an angel of the Lord stopped him. God had seen Abraham's willingness to walk in obedience to and reverence of Him and did not let him sacrifice Isaac. Instead, God provided a ram for Abraham to sacrifice and then promised to bless him and his descendants (Genesis 22:9-18).
True worship comes at a cost. That cost is our lives. We must be willing to give God our lives. In faith, we must obey His Word. In faith, we must surrender all to Him and hold nothing back. And, like Abraham, in faith we must wait on God to provide for all of our needs.