He teaches you all things – 1 John 2:27 TLB.
Let’s look further into our root verse, “But you have received the Holy Spirit, and he lives within you, in your hearts, so that you don’t need anyone to teach you what is right. For he teaches you all things… and so, just as he has said, you must live in Christ, never to depart from him.” We have the Spirit of God living within us, in our hearts, to lead, guide, teach and mentor us. He leads and guides us in righteousness according to the will of the Father. He is the Spirit of the Father, He knows the Father. Holy Spirit teaches us and gives us understanding and knowledge of what He teaches. Our Lord said to the disciples that He had still a lot of things to teach them but was constrained for time, besides they couldn’t take so much in so little a time. However, He sent them and us His Spirit to be with us and to teach us through Him everything He wants us to know. Holy Spirit only says and does what Jesus tells Him. He is the Spirit of Christ. The Spirit keeps us from falling away from Christ by the things He teaches us. He teaches us the truth, and the truth makes us free from the devil’s devices and the deception that’s in the world.
In Isaiah 43:10 the Lord spells out vividly that He has chosen us to understand, believe and know Him. He has given us His Spirit and understanding hearts to accomplish this. We’ve been given the capacity to understand God, to believe God and to know God. There’s no room for ignorance. We can know God, we can understand God, we can believe God. That’s what we were saved, set apart and chosen for. The choice is ours to agree with God and what He’s done for us.
We’re Christians; the people of God, who understand, believe and know Him. But why is it that most of us live and act as if they neither understand, nor believe, nor know Him? Their lives are full of sadness and hopelessness. They are controlled and misled by their minds and desires. They’re more concerned of what they’re going through day by day than they’re of the things of their calling in Christ. They live as if they have not the Spirit of God in their hearts, who teaches, guides, leads and mentors us. Have they received the Spirit we also received with all the saints of God? Maybe, but it doesn’t show at all in their disposition, demeanor and actions. They have not the joy of salvation, nor of the Lord. So what do they have? Ignorance. They refuse Him who should teach and guide them into all truth and liberty, instead they live with presumptions and excuses.