569. Remaining Strands of Skin

Milah 2:3

Some strands of skin invalidate a circumcision and others do not. If a piece of the foreskin remains and covers the majority of the tip’s height, the baby is considered still uncircumcised; this skin invalidates the bris. If only a small piece of skin remains and it does not cover the majority of the tip’s height, it does not invalidate the bris.

Milah 2:4

As long as the mohel is involved in performing the bris, he should go back and remove both the skin that invalidates the bris and the skin that doesn’t. Once he is no longer involved in the bris, he must go back to remove any skin that invalidates the bris but he does not go back to remove skin that does not invalidate the bris. If the mohel does not peel the membrane, it is as if the bris was not performed at all.