Law and Hard Hearts

In chapters 14-25 Justin continues with his barrage on law-keeping. His main arguments are:

(1) The Jews err by not realising the spiritual meaning that the law pointed to.
(2) Prior to Moses there was no law, nonetheless there were still many considered righteous before God.
(3) Justin also explores considerably the concept of the law being given due to the hardness of the hearts of the Jews. Hence, the law is not presented as being essential to God's will, but more of an emergency measure to avoid more sinning and idolatry. To back up his argument Justin makes use of the OT prophetic rhetoric against Israel. However, the tone takes an unfortunate direction when it moves from being a Jewish critique of fellow countrymen, to being appropriated by an "outsider", a Christian.
(4) A more bizarre argument is developed concerning circumcision, which for Justin was established by God to set the Jews aside as the ones who crucified Jesus (therefore, Justin has to ignore the role played by the "uncircumcised" Romans, an unfortunately too common move in Christian theology).