Paul and Barnabas admonished the heathen to turn from “vanities unto the living God.” One cannot trust in the Lord and simultaneously trust in anything else. In order for an individual to be saved, he must repent of trusting in anything other than the Lord. One aspect of repentance involves ceasing to trust vanity and turning one’s faith toward the living and true God. This saving faith needs to become a living faith following salvation. Believers should consistently turn from “vain thoughts” and love the law of God (Psalm 119:113). They should turn from the vain labours that spend their strength for nought (Isaiah 49:4) and be “steadfast . . . in the work of the Lord” knowing that their “labour is not in vain in the Lord” (1 Corinthians 15:58). Additionally, believers should turn from “vain words” (Ephesians 5:6) and hold “forth the word of life” (Philippians 2:16).
Only a foolish man thinks he can hide anything from the Lord. This includes his thought life. The Lord knows all man’s thoughts (1 Chronicles 28:9) which includes the good (Malachi 3:16) and the bad (Psalm 94:11). David expressed this truth to the Lord when he said, “Thou knowest . . . my thought afar off. . . . For there is not a word in my tongue, but, lo, O LORD, thou knowest it altogether” (Psalm 139:2-4). The Lord Jesus Christ often exhibited this capability during His earthly ministry (Matthew 12:25; Luke 5:22; Luke 6:8; Luke 9:47; Luke 11:17). Even the written word of God reveals this ability by being “a discerner of the thoughts and intents of the heart” (Hebrews 4:12).