This is a rhetorical question, for the answer is contained within it. The first clause asserts that God knows us, and thus knows what is good for us. The second clause contains the question, "What does the Lord require?" and finally, the apparently very simple, three-fold set of actions incumbent upon us.
- Do justly. To accomplish this goal, one must first have a sense of justice, then he must have the inclination and will to practice it. Many people, in my opinion, have a "sense of injustice," by which I mean they recognize the hurts or perceived slights performed by others against them, yet they seem to have a truncated notion of what justice is in their dealings with others. A "get even" attitude grows readily in this soil.
- Love mercy. Another action required. It does not tell us to recognize mercy, but to love it. If we love mercy, we are going to behave in a merciful way; we will practice kindness toward others.
- Walk humbly with God. First, this is a requirement to walk, not to sit, or lie about. Then we are told with whom to walk; and we are told how to walk-- with humility. We are clearly not to carry a prideful attitude with respect to our walk with the Lord.
Now this doesn't seem to be so simple, after all. But it is required. The additional good news is that there is apparently not a laundry list of further requirements. Look at the word "but." The implication is that in doing the three required things we are relieved of the burden of making and following nit-picking rules by which to define a godly walk.