The book of Micah is a short but powerful prophecy predicting the fall of Jerusalem and Samaria and offering hope that a 'remnant of Jacob' (Micah 5:7) will later be restored. In chapter 6, God reminds His people of how He has cared for them in the past.
But one thing that is also clear in the book of Micah is that our sacrifices and religious talk or rituals will never be enough to change our hearts for the better. We will always come up short. Our motives will get off track and without His love compelling us and changing us, it's all in vain. External compliance to rules is not as valuable in God's eyes as a humble heart that simply does what is right.
So what does it look like to "act justly, love mercy, walk humbly?" (Micah 6:8)
'Act justly' would have been understood by Micah's audience as living with a sense of right and wrong. In particular, the judicial courts had a responsibility to provide equity for those who are taken advantage of or mistreated and to protect the innocent.
'Love mercy' contains the Hebrew word 'hesed', which means 'loyal love' or 'loving-kindness.' Along with justice, Israel was to provide mercy. Both justice and mercy are foundational to God's character (Psalm 89:14). God expected His people to show love to their fellow man and to be loyal in their love toward Him, just as He had been loyal to them.
'Walk humbly' is a description of the heart's attitude toward God. God's people depend on Him rather than their own abilities (Micah 2:3). Instead of taking pride in what we bring to God, we humbly recognize that no amount of personal sacrifice can replace a heart committed to justice and love.
Micah 6:8 is a concise but powerful field guide to serving God. To act justly, to love mercy, and walk humbly with God ' that's God's answer as to what is good.