This Psalm block is Psalm 90. Although this may not look square, it really is a 12" block. I must have taken the shot at an angle and the pieces themselves give your eye a bit of a wonky view.
Psalm 90:10-17 reads;
The length of our days is seventy years--or eighty, if we have the strength; yet their span is but trouble and sorrow, for they quickly pass, and we fly away. Who knows the power of Your anger? For Your wrath is as great as the fear that is due You. Teach us to number our days aright, that we may gain a heart of wisdom. Relent, O Lord! How long will it be? Have compassion on Your servants. Satisfy us in the morning with Your unfailing love, that we may sing for joy and be glad all our days. Make us glad for as many days as You have afflicted us, for as many years as we have seen trouble. May Your deeds be shown to Your servants, Your splendor to their children. May the favor of the Lord our God rest upon us; establish the work of Your hands for us--yes, establish the work of our hands.