And God knows, by the way, if a certain action will have a bad result; it may not be obvious, but God knows.
God is able to personally communicate with us. And His communication matches with all that He knows.
So, for one thing, it is not going to work to try to make some absolute written moral code. We need how God personally in us communicates and guides us.
How do we know it is really God?

At every moment, we depend on Him to make sure He is really the One guiding and communicating.
"for it is God who works in you both to will and to do for His good pleasure." (Philippians 2:13)
And we can check with His written word to evaluate if He is really the One communicating and guiding. However, of course, there are things not explicitly dealt with in the Bible, but we trust God about this, that He will make sure. And with experience we know the difference between God and what is not God. One scripture which can help with this is > Colossians 3:15 >
"And let the peace of God rule in your hearts, to which also you were called in one body; and be thankful." (Colossians 3:15)
We are commanded to be ruled by God Himself in us, by means of His own peace ruling us. In God's peace we are sharing with Him in His own harmony with almighty immunity against cruel and vain feelings and drives and emotions. Plus, in this peace we share with God in His creativity for how to love any person, at all. Because God is all-loving. So, His peace will take care of us in His all-loving way, not merely making us feel good and safe, for our own selves.
So, included in the covenant of having peace with God who is all-loving is how we are growing in being all-loving in how we live and love. So, one way we can tell something is not God is if it isolates us and has us only or mainly concerned about our own selves and maybe about certain other people we like and hope to use > Jesus deals with this >
"if you love those who love you, what reward have you?" (in Matthew 5:46)
So, we may not always be perfectly sure if God is communicating and guiding, but we can rather easily identify what is not God. And trust Him to make sure; after all, we are not God; so . . . how can we know unless He does His miracle of having us know, which He can >
Jesus does say His sheep hear Him. John chapter 10. This is a miracle, to hear and know Jesus. We trust Jesus to do this with us. And Jesus guarantees this, for whoever is really His sheep > John chapter 10.
Also, God gives us His example, in us >
"Now hope does not disappoint, because the love of God has been poured out in our hearts by the Holy Spirit who was given to us." (Romans 5:5)
If I have really experienced God's own love with His quality and goodness and kind and tender compassion and personal sharing . . . this is my example of how to be in my relating with any and all people. So, this is an absolute moral standard. No law of itself can get humans to do this; we need to be with God in union with us so we can experience Him and this example.
And I think of this > the Bible is our absolute written moral standard. Every scripture can ***somehow*** help us to know how to love and how to live morally.
Using the previous example, sending a child to her room is quite acceptable. But for how long? How do you know when it becomes morally unacceptable?
Well . . . my offering on this is we can be personally guided by God so we do what is right; and He has us doing better than humanly understandable rules ever could tell us to do; because He is God so better than we are, able to have us doing better, even by the moment, than we could imagine, moments before > with such discovering, indeed, in this.
My opinion as one who has never brought up children is > first, spend some time with the child before sending the child to the child's room. Discuss how we are going to make good use of the "time out". One person said his children pray and get right with God, so they can then return from the room; possibly, the child is trusted to know when the child is ready to rejoin the family relating. Of course, we need to have a good family relating atmosphere, as the child's good example, so that when the child becomes wrong, however, the child can see that the child is breaking away from loving as family; and so the child knows what to prepare to return to, and do not come back until you are ready, please. Another person would communicate and negotiate through the closed door, never leaving the troubled child alone.
A pastor I knew would say, "Don't ever have an attitude like that." And that would be it. Attack the cause of what some bad behaving might be. And then the child has a tool, to catch the child's self right when trouble starts in the child. This helps me, anyway > there are things clearly not loving and not in peace, that can get started in me; and already I know I am wrong; and I can trust God to clear that out and restore me to pleasant and soul-resting . . . and all-loving . . . love.
So . . . may be we should not ask what quantity of time is moral, but what quality of atmosphere of family caring and sharing should be the standard. And we grow in this; we discover this, best of all with God.
For moral absolutes for caring and sharing as a family, I would say, God has humility, kindness, patience, creativity so we don't argue or complain, and good example is very important so the child can know readily when the child is going against us by going against our good example, and there is forgiveness but evaluating when and how and why to trust.