There are many great Scriptures that serve as self-examination to see whether or not you are a follower of Jesus Christ. I can think of no better place (in the New Testament) than the Sermon on the Mount for Christians to perform this holy duty. Dr. Martyn Lloyd-Jones has a wonderful statement on this in his book, Studies in the Sermon on the Mount. Here is what he says:
There, then, is the general account of the Christian which is given in the Beatitudes. Do you see how essentially different he is from the non-Christian? The vital questions which we therefore ask ourselves are these. Do we belong to this kingdom? Are we ruled by Christ? Is he our king and our lord? Are we manifesting these qualities in our daily lives? Is it our ambition to do so? Do we see that this is what we are meant to be? Are we truly blessed? Are we happy? Have we been filled? Have we got peace? I ask as we have looked together at the general description. Do we find ourselves to be? It is only the man who is like that who is truly happy, the man who is truly blessed. It is a simple question.
My immediate reaction to these Beatitudes proclaims exactly what I am. If I feel they are harsh and hard, if I feel they are against the grain and depict a character and type of life which I dislike, I am afraid it just means I am not a Christian. If I do not want to be like this, I must be "dead in trespasses and sins"; I can never have received new life, but if I feel that I am unworthy and yet I want to be like that, well, however unworthy I may be, if this is my desire and ambition, there must be a new life in me, I must be a child of God, I must be a citizen of the kingdom of heaven and of God's dear son. Let every man examine himself.