Scripture Study: Why did the Sacrificial System exist?

Scripture (referenced): Exodus 19; Isaiah 1:11; Hosea 6:6; Hebrews 10:1
Scripture (inferred): Genesis 22; Psalm 51:16–17; Galatians 3:19–24; 2 Corinthians 5:19
Themes: progressive revelation; perception vs distance; law as guardian; sacrifice as shadow; God’s nearness
Keywords: sacrificial system purpose; shadow vs substance; God not requiring blood; turning toward God; law and grace