John 16:13
But when He, the Spirit of Truth, comes, He will guide you into all truth (full and complete truth). For He will not speak on His own initiative, but He will speak whatever He hears (from the Father-the messenger regarding the Son), and He will disclose to you what is to come (in the future).

Truth comes from God through the Holy Spirit. When truth comes from God, it is for our benefit and well-being. The devil never tells people positive things and delivers negative images into our brains. God speaks of what is good, trustworthy, and true to lift us up and not break us down.