I think you may have been fed some mushroom food regarding circumcision which would explain what you have posted . I am quite sure that Abraham was told to circumcise his son many, many, many years before anyone invented the idea of ceremonial law. It was actually held in higher esteem and importance than 'keeping the 10 Commandments'.
The Jews are the ones who call it ceremonial law. But I'm not concerned with what you call it. That doesn't matter too much.
The bottom line is.. it was a "sign" of the covenant, not the covenant itself. ( Rom 4:11; Gen 17:11; )
I agree with you about one thing, it was held by many (Especially the Pharisees) to be more important than obeying the commandments.
Acts 15:1; Acts 15:5; Acts 21:21;
Even by this statement, you yourself are separating the commandments from circumcision.
And yes, circumcision is mentioned quite a bit in the NT. (45 times in the NASB) Usually in negative way.
Rom 2:25-29; Rom 3:1; Rom 4:9-12; 1 Cor 7:19; Gal 2:12; Gal 5:2; Gal 5:6; Gal 6:13;Gal 6:15; Titus 1:10; etc...
The commandments are also mentioned quite a bit in the NT (over 60 times in the NASB) Always in a positive way
Matt 5:19; Matt 15:3; Matt 19:17; Mark 7:8; Luke 1:6; John 14:15; John 14:21; John 15:10; Rom 7:12; Rom 13:9; 1 Cor 7:19;
Eph 6:2; 1 Tim 6:14; 2 Pet 2:21; 1 Jn 2:3; etc...
Some verses do both of these things at once.
Rom 2:26-29; 1 Cor 7:19; etc..
John the Baptist and Jesus were both circumcized. ( Luke 1:59; Luke 2:21; )
The "disadvantage of circumcision of the flesh" was many Jews got circumcized thinking that was all that was needed to saved.
(This continued on into the New testament). See, I'm circumcized, I'm good to go. I don't need to worry about the commandments.
Yet Paul called this "false circumcision" ( Php 3:2; ) Paul goes on the say those who keep the commandments are really the
ones who are circumcized of the heart. ( Rom 2:26-28; Rom 2:13; ). Keeping the commandments are more important than circumcision.
You were nothing but a hypocrite if you were circumcized but did not keep the commandments.
It's much the same today.... the advantage is, we don't have to be circumcized in the flesh anymore.
and just like back then.... circumcision means nothing if you don't keep the commandments.
Many Christians today say.. "I'm saved, I believe in Jesus". But they don't keep His commandments.
Are they really circumcized of the heart? Paul says they aren't. ( Rom 2:26-28; )
Anyone could look at their flesh (circumcision) and "believe" they were saved.
But only God can look at the heart and "know" if they are saved.
You're still a hypocrite if you say you know Jesus but don't keep the commandments.
(1 Jn 2:3-4; 1 Jn 3:24; 1 Jn 5:2; etc... )