That is an odd statement to make considering the fact that Paul, as a highly trained scholar of "The Law", claimed he had always followed the Law.
If as you say.....Paul is instructing the newly converted Christians to not observe the Laws and Ordinances of The God of Israel.....then Paul is hereby proved to be a liar.
Rom 3:31 Do we then nullify the Law through faith? May it never be! On the contrary, we establish the Law.
Once it hit me that the sheep Paul were pastoring had never heard of the Law until Paul taught them of it, all of his letters took on a more coherent meaning. It doesn't make sense for Paul to have taught people what the Law was, and then spend years telling them not to follow it.