“No one gets to choose what’s sinful and what’s not except for God. He has the full authority on morality.”
~ Abby Johnson

Correct.
It’s not so much that God chooses what is sinful or not, as much as disunity with Him is sin and causes death… Physical and spiritual.
God is the Author, Sustainer and Source of Life, therefore anything we do outside of His will separates us from that Life. The natural result is death, just as unplugging any device from an outlet would cause it to stop functioning.

I find that people in the church tend to get a little too wrapped up in their version of God; sometimes to the point where when a conflict (or multiple conflicts) arises between what they THINK they know of who YHWH is and who He reveals Himself to be in Scripture arise, they choose the version they’ve got in their minds instead…

Let me ask, how many times as a Christian have you had a good idea, and acted on it, hoping that God will bless your efforts because it’s a nice idea, only for it fizzle… or worse, for it to blow up in your face?

Did you know that as a Christian, it’s not just enough to do Christiany things once you are saved? Jesus warned that many will come to Him in the end pleading with Him, telling Him about all these wonderful things they did in His name, but He will sadly tell them that He never knew them and to depart from His presence! That should sober any churchgoer who thinks that their eternity is secure.

Many people try to sum up God’s Law with the word “Don’t” or maybe “Thou shall not….” Fill in the blank. As a result, many people view His Laws as restrictive instead of what it actually is: Loving. Yeah. Think about it; when you have information about harmful stuff, do you stay silent about it to those you care about, or do you give them a warning? Chances are, if you’re not cruel, you would want to ensure that they avoid the harm they are not aware of.

For instance, when I was learning to drive, I was given the incredible opportunity to go wherever you wanted. With that set of wheels came a seemingly limitless number of possibilities! However, in my optimism about my new horizons, I was not thinking about all the ways my newfound freedom could hurt me. Family and friends, on the other hand, were. I was reminded of the hazards of speeding, passing on those two-lane country roads and even going up blind hills on those barely paved, one lane back roads.