# Your Thummim and your Urim

These were sacred stones the high priest carried on his breastplate and used at times to determine God's will. "Your" refers to Yahweh. 

# your faithful one, the one whom you tested ... with whom you struggled

Moses refers to the tribe of Levi as if it were one man. 

# your faithful one

"the one who seeks to please you."

# Massah

"The name 'Massah' means 'testing.'" (See Deuteronomy 6:16) 

# Meribah

"The name 'Meribah' means 'argue' or 'quarrel.'" (See Deuteronomy 32:51)