Psalm 25:5 - “Lead me in thy truth, and teach me: for thou art the God of my salvation; on thee do I wait all the day.”
The tongue is a precious gift from God to show forth His praise and to hold forth His truth. The underlying principle of the ninth commandment is once again found in God Himself. God is the God of truth. In harmony with the perfection of His own Being, God alone determines the truth and works according to that truth. “For the word of the LORD is right; and all his works are done in truth” (Ps. 33:4).
In addition, as David makes clear in 2 Sam. 2:6, God is the God Who reveals truth. That is why David prays in Ps. 25:4,5: “Shew me thy ways, O LORD; teach me thy paths. Lead me in thy truth, and teach me: for thou art the God of my salvation; on thee do I wait all the day.” God’s Word is truth. It is truth throughout the ages. It is the “scripture of truth” (Dan 10:21), perfectly reliable and trustworthy. It is breathed by theSpirit of truth (John 14:17, 15:26, 16:13), the Holy Spirit. When God sent His Son into the world, His divinely anointed Son Who is one with the Father and the Holy Spirit, the Son said, “I am the way, the truth, and the life: no man cometh unto the Father, but by me” (John 14:6).
It is Christ Who reveals to us the infinite perfections of God — His truth, His holiness, His righteousness, His mercy, His love, His grace. By His death on the cross, Christ is the way unto the Father. To the God of truth, He leads us, bringing us into the fellowship of His covenant life. There is no fellowship with God, apart from the truth. That is why the psalmist sings in Psa 43:3, “O send out thy light and thy truth: let them lead me; let them bring me unto thy holy hill, and to thy tabernacles.” So we read in Psa 145:18, “The LORD is nigh unto all them that call upon Him, to all that call upon Him in truth.” To the truth of God, therefore, we must be entirely devoted. God created us to show forth His praise — in truth. So we are to live and so we are to speak.