In what sense is Jesus a "lamb" and how is that associated with "taking away the sin of the world"?
John 1:29 The next day John seeth Jesus coming unto him, and saith,
Behold the Lamb of God, which taketh away the sin of the world.
The common interpretation of this passage is to understand John to be describing Jesus as a sacrifice for sin, who, by vicariously suffering God's wrath, removes the sins of believers (or, in the case of Calvinists, of the "elect").
This is way off target.
First of all, the sin of the world was not removed when Jesus died. The death of Jesus was associated with the new covenant, which was made with the houses of Israel and Judah and did involved forgiveness of sins. But it was the covenant that provided for the forgiveness of sins while the death was the ratification of the covenant. So the concept of "God's lamb" would not be associated with sacrifice for sins in the minds of John or his contemporaries:
KJV Heb 10:5 Wherefore when he cometh into the world, he saith,
Sacrifice and offering thou wouldest not, but a body hast thou prepared me: Heb 10:6 In burnt offerings and sacrifices for sin
thou hast had no pleasure. Heb 10:7 Then said I, Lo, I come (in
the volume of the book it is written of me,) to do thy will, O God.
Heb 10:8 Above when he said, Sacrifice and offering and burnt
offerings and offering for sin thou wouldest not, neither hadst
pleasure therein; which are offered by the law; Heb 10:9 Then said
he, Lo, I come to do thy will, O God. He taketh away the first, that
he may establish the second. Heb 10:10 By the which will we are
sanctified through the offering of the body of Jesus Christ once for
all. Heb 10:11 And every priest standeth daily ministering and
offering oftentimes the same sacrifices, which can never take away
sins: Heb 10:12 But this man, after he had offered one sacrifice for
sins for ever, sat down on the right hand of God; Heb 10:13 From
henceforth expecting till his enemies be made his footstool. Heb
10:14 For by one offering he hath perfected for ever them that are
sanctified. Heb 10:15 Whereof the Holy Ghost also is a witness to
us: for after that he had said before, Heb 10:16 This is the
covenant that I will make with them after those days, saith the Lord,
I will put my laws into their hearts, and in their minds will I write
them; Heb 10:17 And their sins and iniquities will I remember no
more. Heb 10:18 Now where remission of these is, there is no more
offering for sin.
Secondly, a "lamb" is not a significant animal in the sacrificial system. Adult goats, yes, though the animal that bears away the sin of the Jews on Yom Kippur is the scape goat - the goat that lives and carries the sins off into the wilderness:
In this way he is prefigured as a goat that carries away the sins of the People. But note, it is an adult goat, not a lamb:
KJV Lev 16:21 And Aaron shall lay both his hands upon the head of the
live goat, and confess over him all the iniquities of the children of
Israel, and all their transgressions in all their sins, putting them
upon the head of the goat, and shall send him away by the hand of a
fit man into the wilderness:
Some suggest that a lamb is the figure of the Passover. The animal of the passover was most likely a goat. But even if it were a lamb, it would not be a sacrifice for sin. Sin offerings were not eaten. Their bodies were burned outside of the camp:
Heb 13:11 For the bodies of those beasts, whose blood is brought into
the sanctuary by the high priest for sin, are burned without the camp.
Nor would John have any reason to associate the passover with "taking away sin" as that association was never made in the original passover or the seder.
So in what sense would John and his audience have understood Jesus as "God's lamb"?
The term "God's lamb" is similar to our expression, "God's kid," only without the flippancy. And it is not applied to any in Judaism but only to the Messiah. Furthermore, the figure is one of a violent purger of sin from the earth, not a sacrificial victim as is seen in the apocryphal "Testament of Joseph" (one of the "Testaments of the Twelve Patriarchs"):
Testament of Joseph at
http://www.ccel.org/fathers2/ANF-08/anf08-15.htm
19. Hear ye also, my children, the visions which I saw. There were twelve deer feeding, and the nine were divided and scattered in the
land, likewise also the three. And I saw that from Judah was born a
virgin wearing a linen garment, and from her went forth a Lamb,
without spot, and on His left hand there was as it were a lion; and
all the beasts rushed against Him, and the lamb overcame them, and
destroyed them, and trod them under foot. And because of Him the
angels rejoiced, and men, and all the earth. And these things shall
take place in their season, in the last days. Do ye therefore, my
children, observe the commandments of the Lord, and honour Judah and
Levi; for from them shall arise unto you the Lamb of God, by grace
saving all the Gentiles and Israel. For His kingdom is an everlasting
kingdom, which shall not be shaken; but my kingdom among yogi shall
come to an end as a watcher's hammock, which after the summer will not
appear.
See also http://www.jewishencyclopedia.com/articles/14344-testaments-of-the-twelve-patriarchs
So, taking away the sin of the world is an act of judgment. Think of Sylvester Stallone in "Lamb-O"!
Re 6:16 And said to the mountains and rocks, Fall on us, and hide us
from the face of him that sitteth on the throne, and from the wrath of
the Lamb:
Re 14:10 The same shall drink of the wine of the wrath of God, which
is poured out without mixture into the cup of his indignation; and he
shall be tormented with fire and brimstone in the presence of the holy
angels, and in the presence of the Lamb:
Re 17:14 These shall make war with the Lamb, and the Lamb shall
overcome them: for he is Lord of lords, and King of kings: and they
that are with him are called, and chosen, and faithful.
Note that John expected this purging:
Mt 3:10 And now also the axe is laid unto the root of the trees:
therefore every tree which bringeth not forth good fruit is hewn down,
and cast into the fire.
Lu 3:9 And now also the axe is laid unto the root of the trees: every
tree therefore which bringeth not forth good fruit is hewn down, and
cast into the fire.
When Jesus didn't get with that program, John the baptizer doubted him:
Mt 11:3 And said unto him, Art thou he that should come, or do we look
for another?
Lu 7:19 And John calling unto him two of his disciples sent them to
Jesus, saying, Art thou he that should come? or look we for another?
Lu 7:20 When the men were come unto him, they said, John Baptist hath
sent us unto thee, saying, Art thou he that should come? or look we
for another?
So John did not harbor any expectation of Jesus being a sacrificial animal or of his death providing forensic justification. Instead he was expecting Jesus, as messiah, to overthrow Rome and bringing violent judgment on the wicked of every nation, including and in particular the Jews.