Still, it's a legitimate question. Jesus Christ established His Church on a foundation of prophets and apostles, and Paul stated that this organization was to continue to exist until we all came into the unity of our faith in Christ and understanding of His Gospel. Therefore, the question -- Why do Christians other than the Latter-day Saints not believe in the need for prophets in this day and age? -- is a valid one, and it's one that should be of interest to all Christians.
Well, I'm sorry to have to burst your bubble, but the divisiveness of which you speak has been around since the time of the Apostles, which is precisely why Paul warned about it.
In Ephesians 4:11-13, we read, "And he gave some, apostles; and some, prophets; and some, evangelists; and some, pastors and teachers; For the perfecting of the saints, for the work of the ministry, for the edifying of the body of Christ: Till we all come in the unity of the faith, and of the knowledge of the Son of God, unto a perfect man, unto the measure of the stature of the fulness of Christ: That we henceforth be no more children, tossed to and fro, and carried about with every wind of doctrine, by the sleight of men, and cunning craftiness, whereby they lie in wait to deceive..."
Without the foundation of prophets and apostles in tact, Christianity was doomed to become sectarian before it even got off the ground. During the few few centuries after Christ's death, Christiantiy was extremely fragmented. As a matter of fact, there was no clear line between orthodoxy and heresy until well into the second century, and the Catholic tradition was only a part of a still larger movement. Why? Because the foundation of the Church had crumbled. Christ himself prophesied that the apostles and prophets he would send would be persecuted and even killed. Christianity is not the happy little family we all wish it was. It is highly disfunctional and the Latter-day Saints are no more to blame for this than anyone else.
See, it's this kind of sarcasm that bugs me.
Yes they do, and you won't hear the Latter-day Saints claiming otherwise. Each and every Christian who sincerely tries to emulate our Savior furthers God's kingdom on earth. Unfortunately, that's not what we're talking about here. We're talking about the men God has appointed to act as His spokesmen -- now as in ancient times. So, back to the question, which you still haven't answered: Why do you deny the need for prophets in this day and age? Have we outgrown them? Are we so sophisticated that they would have nothing of value to teach us? Does God no longer care to communicate with us? Is He no longer capable? Is the Bible so crystal clear about everything that we can get all of our answers from reading it? If that's the case, why do you think so many sincere people continue to disagree on so many points of doctrine?
And if Jesus has appointed Popes to lead His Church, the question would be a valid one. Since He didn't, I don't believe it is.