Rock and no water and the sandy road The road winding above among the mountains
I believe this line and passage to be an allusion to Psalm 63. Psalm 63 says "O God, thou art my God; early will I seek thee: my soul thirsteth for thee, my flesh longeth for thee in a dry and thirsty land, where no water is". both mention lack of water and dry land. The line "The road winding above among the mountains" leads me to believe it is a literal representation of a road to God because it says a road above the mountains.