Proverbs regarding God's help to the helpless.
In this proverb, the helpless are in the form of the fatherless. These vulnerable orphans (and widows) are taken under God's special protection.
When these Proverbs were written (and still to this day in many places) it was customary to mark property boundaries with a pile of stones. These landmarks would remain in situ from one generation to the next. Orphaned children would not have the strength to resist anyone who encroached on their land and moved the stones. But God charged Moses with property protection laws that specifically condemned the moving such landmarks (Deut. 19:14; 27:17; Job 24:2; Hos. 54:10).