Hosea 6:6-7 - "For I desire mercy and not sacrifice, and the knowledge of God more than burnt offerings. But like men they transgressed the covenant; There they dealt treacherously with Me."
We dealt treacherously with God at the tree in the garden. God had graciously granted us life, companionship, work, fellowship with Him, every tree to eat from but one. So we wanted that one. We violated His covenant. Some things do not change. While we have a greater covenant now, established in the grace of Christ, we keep sinning against God’s grace.
We sacrifice ourselves and sacrifice ourselves, working ourselves to the bone, thinking it is what God wants, when He really wants us to get beyond our bony selves and show mercy to others. God wants His people to come to Him, to seek Him and know Him, more than He wants worker bees for His Kingdom. He does want both, but we tend to substitute work for relationship, labor for love. The goal of your sacrifice is not brownie points for you, but mercy given to others.