Psalms 25:10

In all His dealings Jehovah proves His loving purpose and His faithfulness to His promises to those who on their part are faithful to Him, keeping the covenant inaugurated by circumcision (Genesis 17:2 ff.), and ratified at Sinai (Exodus 19:5; Exodus 24:7-8); of which the Ark of the Covenant (Numbers 10:33) was the outward sign, and the Ten Words written on the Tables of the Covenant were the fundamental charter (Deuteronomy 9:9). Jehovah's testimonies are His commandments, as witnessing to His will. See note on Psalms 19:7.

mercy and truth R.V. lovingkindness and truth. So He proclaimed Himself to Moses, as a God -plenteous in lovingkindness and truth" (Exodus 34:6).