The prophecies of the Lord Jesus Christ in Matthew chapter 13 concerning the parables of a) Wheat and false Wheat, b) Mustard seed and c) Leaven, have already been fulfilled. The so-called Christianity had become the largest religion in the world. The true gospel, the kingdom of the God has been hidden and not taught and preached in public for some time. Anyone in any where in the world can start a ministry to do works on behalf of the Lord Jesus Christ. And anyone can interpret the word of the God in his/her own way. This is total lawlessness. The translated word "Christian(s)" in Greek is "Christianos" and it occurred in the New Testament scriptures only three times. Yet it is probably the most abused, distorted and misused word today in the so-called Christian world. This Book is released to reveal "Who is a Christian?" according to scriptures. And for those who are truly seeking the truth, three other booklets are released to reveal according to scriptures, a) How a profession believer can examine himself or herself if he/she belongs to the Lord Jesus Christ, b) How important it is for professing believers to hear the voice of the Lord Jesus Christ, and c) How a professing believer can hear the voice of the Lord Jesus Christ, the true Shepherd(or Pastor). In the confused situation in the present Christian world, a true believer must struggle through the environment he/she is in, in order not to be led astray and be lost forever as warned by the Lord Jesus Christ in Matthew chapter 24, Mark chapter 13 and Luke chapter 21 - the relevant scriptures applicable to believers in the last days, which we are in. Unless a true believer stands solidly in the truth(or the word of the God), he/she will be shaken in the light of the onslaught of so much false teachings, so many false prophets, false teachers and false preachers and the gathering of so-many false believers in large congregation. This book should be read together with Book Number 11(Seven letters to the seven churches in Asia) for serious believers to have a sound understanding of the present environment and situation concerning the gospel of salvation, the kingdom of the God.