And other sheep I have, which are not of this fold: them also I must bring, and they shall hear my voice; and there shall be one fold, and one shepherd. (John 10:16)
Naturally, there were more people in the world than just those at Jerusalem and the surrounding areas. To these people, Christ’s gospel, and His doctrine, would need to be taught. And it would be taught, not just by the mouth of Christ’s servants, but by His own voice.
After His resurrection, Jesus Christ appeared to the ancient people of the Americas. He taught them,
And verily I say unto you, that ye are they of whom I said: Other sheep I have which are not of this fold; them also I must bring, and they shall hear my voice; and there shall be one fold, and one shepherd. (3 Nephi 15:21)
The people of the Book of Mormon saw Christ, and He ministered unto them. They heard His voice and learned His doctrine. God loves all His children, so why would He not send His Son to minister unto others? This is proof that He has done so. I know that Jesus Christ appeared in the Americas, as well as other places, to gather together His fold.
I know that God is a living God. His works and His love never cease, and He will always show this to us. The Book of Mormon is one major way in which He has done so. Of this I bear witness, in the name of Jesus Christ.