Come, Follow Me: April 19-25 - Doctrine & Covenants 41-44
The phrase "my law to govern my church" comes from Doctrine and Covenants 42:59. The church was being established in Kirtland, Ohio and numerous converts were flocking to the area. In earlier revelations, the members had been told by the Lord that the law would be given in Ohio, and these sections are the fulfilment of that promise.
Doctrine and Covenants 41
"He that receiveth my law and doeth it, the same is my disciple.”
It's fairly simple - hear and receive the law, and then follow it. And if you choose not to follow it, verse 5 says you "shall be cast out". Of course, there is always the
Doctrine and Covenants 42
God’s laws govern His Church and can govern our lives.
Doctrine and the accompanying principles teach us the path to follow. President Nelson has called it the Covenant Path and I think that is a good description of the idea that we are making a promise to follow and the guidance is given on where to go. No one is forced to make the choice, and as you see in the world today you are free to leave the path at anytime. But following that path will lead us to the "Tree of Life" and exaltation.