No, the Old Testament or Old Law is not abrogated.
According to the Gospel of Matthew, Jesus did not come to abolish the old law but to fulfill instead.
17 “Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them. 18 For truly I tell you, until heaven and earth disappear, not the smallest letter, not the least stroke of a pen, will by any means disappear from the Law until everything is accomplished. 19 Therefore anyone who sets aside one of the least of these commands and teaches others accordingly will be called least in the kingdom of heaven, but whoever practices and teaches these commands will be called great in the kingdom of heaven. 20 For I tell you that unless your righteousness surpasses that of the Pharisees and the teachers of the law, you will certainly not enter the kingdom of heaven." (Matthew 5:17-20 NIV)
Unfortunately, many Christians don't follow Jesus' rule, but they follow Apostle Paul, which he believed that the Old law was abolished.
However, Muslim scholars don't trust Paul because he actually did not follow Jesus' rule. Visit:
http://www.answering-christianity.com/abdullah_smith/anti_christ_paul_1.htmhttp://www.answering-christianity.com/abdullah_smith/anti_christ_paul_2.htmhttp://www.answering-christianity.com/adeel_khan/Why_Paul_should_not_be_trusted.htm