The meaning of your question is unclear. I can think of a few possible
interpretations of this question:

1. Are the teachings of the Old Testament followed by certain religious
groups today?

2. Is it correct to teach that Christians should be following all or part
of the Old Testament Law?

3. Does the New Testament require that followers of Jesus follow Old
Testament laws?

4. Are there principles taught in the Old Testament which would apply for
followers of Jesus Christ today?

My best guess, based on experience of many asking similar questions, is
that probably question #2 is what you are really getting at.

Having said that, let me answer question #1. Yes, certainly there are many
groups who teach following of all or part of the Old Testament. First of
all, obviously many Jews would teach that one should follow the Old
Testament laws!! Of course, there are few if any Jews who apply even a
minority of these laws to themselves. Jews certainly do not practice
animal sacrifice any more. Neither do they follow such teachings as
Sabbath years and Jubilee years. Nevertheless, all Jews teach that at
least some of the Old Testament laws are still in force. Besides, there
are a number of denominations whose members would identify themselves as
Christians who teach that significant parts of the Old Testament law apply
to disciples of Jesus. The most common, of course, is to teach that the
Ten Commandments are still in effect. Interestingly, most of those who
would still teach the Ten Commandments as binding, do not include
observance of the Sabbath, or would teach that Sunday worship is the
Christian “Sabbath.” The Seventh Day Adventist denomination, as well as a
number of other Adventist groups and other religious groups as well would
teach their followers that significant parts of the Old Testament laws
apply to followers of Jesus today. Most common is to teach that Saturday,
or the Jewish Sabbath is still in force for Christians. This, of course,
is where the term “Seventh Day” comes from. There are a significant number
of other OT laws which Adventists teach their followers are required as
well, such as not eating pork, not eating blood, refusing blood
transfusions (a Jehovah’s Witness teaching) and so forth.

Now to question number two. Jesus said that he came, not to abolish the
Law, but to fulfill it (Matthew 5:17). Jesus is saying here that he
fulfilled the righteous requirements of the Old Covenant law through his
perfect life. Jesus himself obeyed the Law in his own lifetime, at least
in part so that we would not have to do so. The New Testament books which
most strongly deal with the false teaching that disciples of Jesus must
obey the Old Covenant law are Galatians and Colossians. Consider
Colossians 2:13f. “And when you were dead in your transgressions and the
uncircumcision of your flesh, He made you alive together with Him, having
forgiven us all our transgressions, having cancelled out the certificate
of debt consisting of decrees against us and which was hostile to us; and
He has taken it out of the way, having nailed it to the cross. When he had
disarmed the rulers and authorities, He made a public display of them,
having triumphed over them through Him. Therefore let no one act as your
judge in regard to food or drink or in respect to a festival or a new moon
or a Sabbath day… Here one clearly sees the Bible teach that the
requirements of the Old Testament were nailed to the cross along with
Jesus himself. The requirements were taken away. Which of the requirements
should we then be required to keep? None!!! The Ten Commandments are no
longer in force, as we are no longer under the Old Covenant. It just so
happens that most of the Ten Commandments are still applicable as they are
taught by Jesus himself. One is still not to murder or to covet his
neighbor’s wife! Galatians teaches that if anyone is trying to be accepted
by God through the following of the Old Testament laws (especially
circumcision in the context of Galatians), then one has fallen away from
grace and thrown away their salvation. These are extremely strong words
(Galatians 3:10, Galatians 5:3,4, etc.) The question is simple. Either
followers of Jesus are required to keep the commandments of the Old
Covenant, or they are not. There is not a single person who is consistent
in demanding that Christians follow the entire Old Testament law, not even
the Seventh Day Adventists. How do they decide which part of the Law
disicples of Jesus should follow? There is no conceivable way to decide
such a thing based on New Testament scripture. The answer is supplied by
the books of Colossians and Galatians (and many other passages as well,
such as Romans 7, etc…) Jesus Christ fulfilled the righteous
requirements of the Old Covenant. We are not under the law of sin and
death, but under the law of Christ.

As far as question number four is concerned, the Old Testament serves as
an awesome example of principles of how to remain faithful to God. One
finds great wisdom in the Proverbs–not laws but advice for godly living.
One finds great example of how to have a close, vibrant relationship with
God in the Psalms. The Psalms are not a source of doctrine, but of example
for being close to God. The many stories in the Old Testament are great
examples of how we stand before God both as individuals and as a group.
Consider 1 Corinthians 10:11 and the context, where it teaches that the
Old Testament serves as an example to us, not of doctrine but of correct
and righteous living. Romans 15:4 teaches that the Old Testament serves as
an encouragement to us to obey God. One could mention many other passages,
both in the Old and the New Testaments which show the great usefulness of
the Old Testament scriptures. What changed at the time Jesus was crucified
and raised from the dead is that we who follow Christ are no longer
required to obey the Old Testament laws in order to obtain a saved
relationship with God. We must repent, but our total faith and trust in
Jesus and be baptized into Christ in order to enter a saved relationship
with God (Romans 8:1,2).

John Oakes, PhD