RobH_en_tn/psa/119/120.md

My body trembles in fear of you

Here "body" represents the whole person. Alternate translation: "I shake because I fear you" (See: rc://en/ta/man/translate/figs-synecdoche)

I am afraid of your righteous decrees

It is implied that the writer is afraid of God's righteous decrees because the writer knows that God punishes those who disobey his decrees. You can make the full meaning of this statement explicit. (See: rc://en/ta/man/translate/figs-explicit)