To understand this verse, one should first look at Deuteronomy 18:15-19 (KJV):
15 The LORD thy God will raise up unto thee a Prophet from the midst
of thee, of thy brethren, like unto me; unto him ye shall hearken; 16 According to all that thou desiredst of the LORD thy God in Horeb
in the day of the assembly, saying, Let me not hear again the voice of
the LORD my God, neither let me see this great fire any more, that I
die not.
17 And the LORD said unto me, They have well spoken
that which they have spoken.
18 I will raise them up a Prophet
from among their brethren, like unto thee, and will put my words in
his mouth; and he shall speak unto them all that I shall command him.
19 And it shall come to pass, that whosoever will not hearken
unto my words which he shall speak in my name, I will require it of
him.
The "prophet" referred to in John 1:21 is the same Prophet that is spoken of in Deuteronomy 18. For many years, the Jews had been looking for this Prophet to come. This Prophet is Jesus Christ, the Son of God. Look at John 6:14 (KJV):
14 Then those men, when they had seen the miracle that Jesus did, said,
This is of a truth that prophet that should come into the world.
This was after Jesus did the great miracle of feeding 5,000 with 5 loaves and 2 fishes. These people basically said that the miracle that Jesus did gives evidence to Him as being the "prophet."
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is he the prophet
agin when Mohammad born , and that makes sense if we match it with john 1 ,21 .