What is the ruling on circumcision for a new Muslim, and when should he be circumcised?

Circumcision is obligatory for the born Muslim and the new Muslim. The new Muslim must be circumcised as soon as he embraces Islam. However, if it is in the best interest to delay commanding him to be circumcised, out of fear that he might flee from Islam due to the instability of faith in his heart, then there is no harm in that, because the harm of delaying circumcision is less severe than the harm of his apostasy from Islam.