During a Apologetics presentation, a Muslim student asked Ravi Zacharias if Christianity lacks a comprehensive Law(like Islam and Judaism) how can it bring order to society? Ravi Zacharias explained to Him that Christianity does not nullify or lack moral Law it transcends it and brings you to the Spiritual reality of the Law (A clip of the exchange is at the bottom of the post).
This is a objection from many Muslims who see the lack of volumes of Fiqh books listing innumerable do's and don'ts as a draw back of Christianity. Yet if one reads Matthew chapter 5 verses 17-48, Jesus never told His disciples to abandon Moral Law but instead they needed to exceed the letter of the Law. Now I think we all know that trying to adhere to God's written standards of morality are hard enough, so how can we ever hope to exceed them? This can not be done by one's own willpower(And we shall discuss why later) but by being Spiritually reborn and being lead by the Holy Spirit from the inside, to want to be more then just moral(see John 3:3).
As for the other aspects of the laws of Judaism they were not done away with, but instead their purpose was fulfilled in the life and person of Jesus Christ. As he said to the Jews..
"You search the Scriptures because you think that in them you have eternal life; it is these that testify about Me" John 5:39 (NASB95)
A commentary on this verse explains it in the following terms.
"The Jewish religious leaders studied the Old Testament with great diligence. They believed that if one could comprehend the words of the text, he would gain a share in the world to come. They considered those ignorant of the Law to be under a curse (7:49). Similarly many people today think Bible study is an end in itself rather than a function leading to the knowledge of God and godliness, Somehow a veil was over the minds of these Jewish scholars (2 Cor. 3:15), and they failed to see that Jesus is the Promised One. He is the fulfillment of the Old Testament sacrificial system.."
Walvoord, J. F., Zuck, R. B., & Dallas Theological Seminary. (1983-). The Bible knowledge commentary : An exposition of the scriptures (Jn 5:39–40).
The Bible never taught that anyone could justify themselves before God by doing the letter of the Law, it has always been by True Faith, Hope and Trust(In God not ones keeping the Law) that a person was justified before The Holy God.
Now that no one is justified by the Law before God is evident; for, “THE RIGHTEOUS MAN SHALL LIVE BY FAITH.” Galatians 3:11 (NASB95)
And this verse is quoting form the Old Testament, so we know this was always so...
“Behold, as for the proud one, His soul is not right within him; But the righteous will live by his faith." Habakkuk 2:4 (NASB95)
To make a application to our day, the proud one is in stark contrast to the one who lives by Faith, for one trusts in their own-self and the other doesn't trust in their self at all, but in God alone.
You who boast in the Law, through your breaking the Law, do you dishonor God? Romans 2:23 (NASB95)
The person who is self righteous and believes they will be-able to be justified because of their supposed adherence to Laws, must recall that they also are total Sinners who break the same Laws they boast in! So if you feel safe from God's judgement because of your "religiosity", then really you have been condemned by your Sins already, God will be judging the inside not the mere outside unlike man.
No, it is only in Jesus Christ that we can find the Power to not just follow a list of Laws, but be-able to Live a life of living Faith that truly pleases God. Christianity is not a step down from the Law its a unmerited act of Grace from God who has given us something superior to every religious book of rules and rituals, the opportunity to have a direct relationship with the Divine through Jesus Christ.
No longer will you need to try and access God through repetitive rituals done at shrines made by human hands, but you yourself will be a Living shrine of God, and you will be His living Book testifying to the world about Him, because His Spirit will come and live in inside you, and you will know Him intimately.
“Behold, days are coming,” declares the LORD, “when I will make a new covenant .... I will put My law within them and on their heart I will write it; and I will be their God, and they shall be My people....They will not teach again, each man his neighbor and each man his brother, saying, ‘Know the LORD,’ for they will all know Me, from the least of them to the greatest of them..”
Jeremiah 31:31,33,34 (NASB95)
being manifested that you are a letter of Christ, cared for by us, written not with ink but with the Spirit of the living God, not on tablets of stone but on tablets of human hearts. 2 Corinthians 3:3 (NASB95)
How many lists of Laws, methodologies and rituals has mankind tried to employ to create utopia on earth? All of them have failed, not because they did not contain any goodness..No, we can be safe in saying all the worlds religions and ideologies contain some good, but the root of the problem is in us, its the Sin that lives in man that has caused the failure. This call of Christianity is not a another call to buckle down and get yourself right or face the Hell fire, it's a call to come and be radically transformed from the inside out, and then we will be ready to receive the Utopian existence man has always yearned for all these eons.