457. Tzitzis Made from Existing Tzitzis

Tzitzis 1:14

If a person passes strings between the holes on two corners of a garment, ties them properly, and then separates them, the tzitzis are invalid. This is because they were not valid at the time they were tied, since two corners were connected by the strings. The strings were cut, making two tzitzis, so this is like making tzitzis from those that already exist.

Tzitzis 1:15

Let’s say that a person ties tzitzis over existing tzitzis. If his intention is to nullify the first tzitzis, then if he removes the first tzitzis, the second tzitzis are valid. However, if his intention is to add a second set of tzitzis, then the tzitzis are invalid even if he removes one set. When the second tzitzis are added, both sets are invalidated. Therefore, when he removes the extra tzitzis, the ones remaining are invalidated because of making tzitzis from already existing tzitzis, since the way in which it existed before was not valid.