I was circumcised, without being asked if that's my wish, about the same time I was baptized the first time, shortly after I was born. My brother, Jim, wasn't circumcised.  I can only surmise that I was, because the military hospital, where I was born and when I was born recommended it, so my parents went along. This occurred early January 1929.

Paul, then Saul of Tarsus was also circumcised, as were all the Jews then, and it continues to this day, for all of the Jewish faith.  It's done on the 8th day, in a somewhat celebratory manner. 

Why?

Because God decreed it, starting with Araham, as a sign of the chosen tribe.  Imagine the pain involved, by Abraham, experiencing this at his advance age!

Circumcision was a visible sign of the covenant between God His chosen people. A sign that sinfulness is removed from their heart.

The twelve Apostles and  their acolytes insisted that those pagans, proselyted into their religious faith, that espoused by Jesus in the flesh, would be circumcised, and live by the other laws peculiar to the Jews.

 But not Paul. He believed that his pagan followers would be circumcised in the heart, and the physical act was not required.  This was no doubt decided upon, after one of his sessions with the Spirit of Christ.  I'm sure that this was not an arbitrary choice by Paul. I'm also certain that, not having to endure the physical pain, aided in his mission to recruit believers.

There was a real donnybrook afair, partially due to this not being a requirement by those who would follow Paul, during the meeting with the other Apostles in Jerusalem, when Saul/Paul was seeking acceptance by James, Peter and the others, but he persevered and and was accepted.  

An aside..he was told that none of the requirements involved in proselyting would be necessary, only that they should abstain frome eating the food that had been used to worship idols.

I wouldn't think that would be much of a hardship. They were not forbidden from eating those foods, considered "unclean" by the Jewish laws.

So, circumcised physically or no, we believers need only remember that we are circumcised in the heart, and there need be no visible sign to show the covenant between God and us, and that we are chosen to follow Jesus the Christ into the heavens..paulnbob