Certainly, circumcision is beneficial, if you observe the law. But if you are a betrayer of the law, your circumcision becomes uncircumcision
Other versions
King James Version
For circumcision verily profiteth, if thou keep the law: but if thou be a breaker of the law, thy circumcision is made uncircumcision.English Standard Version
For circumcision indeed is of value if you obey the law, but if you break the law, your circumcision becomes uncircumcision.New International Version
Circumcision has value if you observe the law, but if you break the law, you have become as though you had not been circumcised.