He would have spoken about Moshiach.

Too many to mention, people identified as prophets (either self-proclaimed or proclaimed by their followers). We might start with the leaders of the Christian Gnostics. We can mention the leader(s) of the Cathars. We can mention the Millennial prophets (those who taught that the year 1000 would be the year that Satan would be unbound and mislead all the World and, shortly after, Armageddon - in contradiction to what "the church" at the time taught.). We can mention the leaders of the flagellants. We can mention the Adventist prophets (both those of the 19th century and later ones, up to modern times, such as Camping and van Impe, who claim to know the time of Christ's return), the many (many) Mormon prophets, the Black Hebrew Nationalist prophets, the Shaker prophet(s), the Rastafarian prophet(s). etc. etc. etc. (I'm overlooking a LOT.) Of course we can also mention prophets of other religions that (intentionally) draw many Christians away from Christianity, such as Muhammad, Moon, Jim Jones, etc.

The epistle of I John states that it is possible to identify those who are not “of God". I John 4:1 “Beloved, believe not every spirit, but try the spirits whether they are of God: because many false prophets are gone out into the world.” A key to understanding this is found in John chapter 8, where Jesus expanded on this, as he spoke to those who opposed his ministry. John 8:42,47 “Jesus said unto them, If God were your Father, ye would love me: for I proceeded forth and came from God; neither came I of myself, but he sent me. He that is of God heareth God's words: ye therefore hear them not, because ye are not of God.” Jesus explained that those that are "of God" are those that hear God's words, and come to know and love Jesus Christ. archive.org/details/bibletellsmeso01wier/page/20 In the process, he identified those who were "not of God" to everyone with ears to hear. These men were "antichrist" (as mentioned in I John 4) because they were in opposition to Christ. As we grow in our understanding of I John, we enhance our fellowship with God and other believers. I John 1:3 “That which we have seen and heard declare we unto you, that ye also may have fellowship with us: and truly our fellowship is with the Father, and with his Son Jesus Christ.”

Probably one of the biggest was Augustine of Hippo when he brought Gnosticism into the church. He was a student of Manicheism before.

First let's look at the context of the passage, in verse 3 the disciple asked Jesus about the end of the world...KJV. In verse 9 Jesus is talking to his disciples at the end of times, and if you notice that He said that the false prophets would come in His name. So the false prophet would have to acknowledge Him, but as any false friend this prophet would use Jesus name to mislead and detract from his teachings. Now let's look at verse 14 which talks about the preaching of the "Gospel of the Kingdom shall be preached in all the world for a witness unto all nations" KJV...So if Jesus main objective was the preaching of God's Kingdom, then that would be the main objective of his true disciples, so then the false prophets would be those that would use his name to; as verse 11 says "deceive many"...KJV, and detract from the massage that God's Kingdom is the only salvation for mankind. If you would like more information on this or other Bible topics please visit JW.org

2 Peter 2

There have been at least thousands throughout history. There's probably several within 100 miles of you right now.