"Fear will keep the systems in line, Fear of this Battle Station" - Governor Tarkin
"There is no fear in love, but perfect love casts out fear. For fear has to do with punishment, and whoever fears has not been perfected in love." - 1 John 4:18
As a Christian, as a Saint, I need no threats of the Law. The third use of the Law speaks to the New Man - and there are no threats, no punishments, no "or elses" attached.
As a fallen man, as a Sinner, I need to be warned, I need the threats and warning to curb me from being the slob that I would be if left to my own sinful druthers. The first use of the law speaks to this.
If you are attaching punishments, threats, or consequences, you are no longer speaking the 3rd use of the Law, even if you are speaking to Christians.