He doesnt. 1st Corinthians 7:19 - Circumcision is nothing, and uncircumcision is nothing The practice was an outward sign that you chose to live a repentant holy life. It was only a "type". The antitype is to be circumcised in the heart. Romans 2:25-27 25 For circumcision verily profiteth, if thou keep the law: but if thou be a breaker of the law, thy circumcision is made uncircumcision. 26 Therefore if the uncircumcision keep the righteousness of the law, shall not his uncircumcision be counted for circumcision? 27 And shall not uncircumcision which is by nature, if it fulfil the law, judge thee, who by the letter and circumcision dost transgress the law? The physical act is nothing. It was to be a spiritual act. The former was just symbolic.