Lucifer's Restriction

Lucifer, from what we can tell, has some form of divine restriction from harming sinners. If that is the case, why would it allow for his power to be used as a battery for another weapon? Wouldn't that be exactly the same as forming a sword like he does or if he uses it as some projectile weapon/dropping like a huge? Couldn't he now just connect himself to anything to make it a weapon and then punish powerful sinners by himself via dropping a building on a guy. Maybe lucifer is just dumb.

I don't even particularly like the restriction as it doesn't even make sense. Why is his restriction so unique compared to other divine creatures? If causing humans to sin was so bad, why wouldn't Adam or any of the angels killing people's eternal souls also be seen as bad? Especially with what we know about redemption.