“A Dictionary of Early Christian Beliefs”

by David W. Bercot.
Starting on p. 167 under the entry CIRCUMCISION the author quotes Rom 2:28,29 and Gal 5:2,3
then the following Church fathers (emphasized key words in bold):

“He declared that circumcision was not of the flesh. Rather, [the Jews] transgressed because an evil angel deluded them…. But you will say, “Yes, truly the people are circumcised for a seal.” Yet, so is every Syrian, Arab, and all the priests of idols, as well. So are these people, then, also within the bond of His covenant? In fact, the Egyptians practice circumcision, too.” — St. Barnabas 70-130 AD

“The inability of the female sex to receive fleshly circumcision proves that circumcision proves that circumcision was given for a sign. It was not given as a work of righteousness.” — St. Justin Martyr 160 AD

[Speaking to Jews:] “Your first circumcision was and is performed by iron instruments, for you remain hard-hearted. However, our circumcision is the second circumcision, because it has been instituted after yours. It circumcises us from idolatry and from absolutely every form of wickedness.” St. Justin Martyr 160 AD

“God gave circumcision as a sign, not as the completion of righteousness.” St. Irenaeus 180 AD

“We do not follow the Jews in their peculiarities in regard to food, nor in their sacred days, nor even in their well-known bodily sign.” Tertullian 197 AD

“Let the one who contends that…circumcision on the eighth day is still to be observed because of the threat of death,…prove to us that in ancient times righteous men kept the Sabbath or practiced circumcision, and were thereby made “friends of God.” God created Adam uncircumcised and non-observant of the Sabbath. Why did God not circumcise him—even after his sinning—if circumcision purges?…Furthermore, God freed from the deluge Noah, who was uncircumcised and did not observe the Sabbath. Enoch, too, God transported from this world, even though that most righteous man was uncircumcised and did not observe the Sabbath…Melchizadek also, “the priest of the most high God,” although uncircumcised and not observing the Sabbath, was chosen to the priesthood of God.” Tertullian 197AD

“Therefore, for all those who had been delivered from the yoke of slavery, he would earnestly have to obliterate circumcision, the very mark of slavery.” Tertullian 197 AD

“Celsus [a pagan critic] does not condemn circumcision as practiced by the Jews. Rather, he claims that this practice was derived from the Egyptians. He thus believes the Egyptians rather than Moses, who says that Abraham was the first among men to practice this rite….However, the rite of circumcision began with Abraham and was discontinued by Jesus, who desired that His disciples should not practice it.” Origen 248 AD

Probably [circumcision] was performed on account of the hostility of some angel towards the Jewish nation, who had the power to injure those of them who were not circumcised. Yet, he was powerless against those who had undergone the rite. This may be said to appear form what is written in the book of Exodus, where the angel was able to work against Moses before the circumcision of Eliezer, but could not do anything after his son was circumcised….However, this power lasted only so long as Jesus had not assumed a human body. But when He had become human and had undergone the rite of circumcision in His own person, all the power of the angel was abolished over those persons who practice the same worship, but are not circumcised. For Jesus reduced it to nothing by His unspeakable divinity. Therefore, His disciples are forbidden to circumcise themselves. They are reminded: “If you become circumcised, Christ will profit you nothing.”” Origen 248 AD

“Concerning the abolishing of circumcision, Isaiah prophesied in this manner….”Circumcise yourselves to the Lord your God and take away the foreskins of your heart.”” Lactantius 304-313 AD

“The circumcision of the flesh is plainly irrational. For, if God had so willed it, he could have formed man from the beginning without a foreskin. However, [fleshly circumcision] was a figure of this second circumcision, signifying…that we should live with an open and simple heart.” Lactantius 304-313 AD

“I, who have been made rich by the grace of God, and who have obtained the circumcision of the heart, cannot by any means stand in need of that most profitless circumcision.” Disputation of Archelaus and Manes 320 AD