'Teaching' in the Bible

My dearly-loved friends, it is no new command that I am now giving you, but an old command which you have had from the very beginning. By the old command I mean the teaching which you have already received.

As for you, let the teaching which you have received from the very beginning continue in your hearts. If that teaching does continue in your hearts, you also will continue to be in union with the Son and with the Father.

As for you, the Spirit which he gave you is still in you, and you have no need of any teacher; but as his Spirit gives you teaching about all things, and is true and not false, so keep your hearts in him, through the teaching which he has given you.

By this we know [without any doubt] that we love the children of God: [expressing that love] when we love God and obey His commandments.

For the [true] love of God is this: that we habitually keep His commandments and remain focused on His precepts. And His commandments and His precepts are not difficult [to obey].