# the firm foundation of God stands

"God's truth is like a firm foundation" or "God has established his people like a building on a firm foundation" or "God's faithfulness is like a firm foundation." 

# this inscription

Possible meanings of "inscription" are 1) words written into stone with a chisel or 2) words impressed in wax by a king's ring. 

# who names the name of the Lord

"who calls on the Lord" or "who says he is a believer in Christ" 

# depart from unrighteousness

"stop being evil"