You have stated the following opinion of Rebbe Akiva Eiger, Z"L for which I need the citation, cannot locate,and would like for you to send it to me along with your comment of how the mitzvah was not fulfilled but the baby is fully circumsized, thank you:
(a) REBBI AKIVA EIGER cites the ROSH (#5) who proves that if Milah is done to a baby before the eighth day, the baby does not need any further Milah or Hatafas Dam Bris when the eighth day arrives. Although the Mitzvah of Milah was not fulfilled, the baby is considered fully circumcised. Accordingly, the act of Milah was indeed a constructive one.
(b) Rebbi Akiva Eiger further explains that from the Gemara in Kerisus (19b) it is evident that the Mishnah here follows the opinion of Rebbi Shimon, who maintains that one is Chayav for the Melachah of Chovel (making a wound) even when his act is Mekalkel.
Eric Solowitch, Brooklyn Heights, Ohio USA
Dear Eric,
(a) The citation you are looking for is in CHIDDUSHEI RABBI AKIVA EIGER SHABBOS 135a. There he quotes TESHUVAS SHA'AGAS ARYEH (#52) that the reason ROSH(#5) states that if Milah was done before the 8th day that the baby needs no further Milah or Hatafas Dam Bris when Day 8 arrives is because Milah before Day 8 is equivalent to Nichras HaGid i.e. the organ was totally cut off before Day 8 arrived. Therefore the Mitzva was not performed i.e. if one cut off the organ instead of performing Milah one clearly did not fulfil the Mitzva but nevertheless there is nothing more that can be done on the eighth day because it is obviously meaningless to do Milah or Hatafas Dam Bris on a baby which has no organ.
(b) The second citation you mentioned is found in CHIDDUSHEI RABBI AKIVA EIGER SHABBOS 137a (and is also printed in the Mishnayos in TOSFOS R.A.E. to Mishnah 4 in ch. 19). TOSFOS YOM TOV cites RAMBAM that even though the Bris should have been done after Shabbos but was erroneously done on Shabbos (i.e. before the eighth day) nevertheless he is culpable because this is considered a constructive act since the baby is thereby considered circumcised as he requires no further circumcision. However R.A.E. asks on this from KERISUS 19b which states that our Mishnah maintains that the act is considered "Mekalkel" i.e. destructive.
KOL TUV
R. Dovid Bloom