666. The Final Hammer Blow

Shabbos 10:15

Demolishing even the smallest amount renders one liable provided that one demolishes with the intention to build. If one’s intention is purely destructive, he is not liable. One who demolishes a permanent tent or separates attached pieces of wood is liable for performing a subordinate labor of demolishing so long as his intention is to facilitate eventual improvement.

Shabbos 10:16

Making the final hammer strike renders one liable; any activity that signifies the completion of a task renders one liable as a subordinate labor of making the final blow. Therefore, one who blows a glass utensil, makes a design - or part of a design - on a utensil, sands a utensil, or makes even the smallest hole in a piece of wood, a building, a piece of metal or a utensil, is liable for a subordinate labor of completion. One would not be liable for making a hole unless things can be moved both in and out through it.