Old Testament

BAPTISM OF PURIFICATION:
Old Testament washings were almost always for those of the already believing community. They symbolized cleansing from sin and guilt. Whereas sacrifices were to atone for acts of sin, washing or bathing seems generally associated with cleansing from a sinful or otherwise unholy condition.

National Exodus 19:10-11:
Before God spoke to the Israelites from Sinai, he commanded them to consecrate themselves, wash their clothes and be ready by the third day, when he would appear to them.
Priestly Leviticus 8:6-9:
At the consecration of the priests Moses brought Aaron and his sons forward and washed them with water.
Individual Leviticus 14:8-9:
A person who had recovered from an unclean skin disease had to wash his clothes , shave off all his hair and bathe with water to be ceremonially clean.

Intertestamental and Rabbinic Judaism

BAPTISM OF PURIFICATION:
The Jewish community at Qumran (probably an Essene group ca. 2nd century B.C. - 1st century A.D. that produced the Dead Sea Scrolls) used washing as a rite of cleansing. From The Damascus Rule (translation from The Dead Sea Scrolls in English , Geza Vermes, tr.):
Qumran

"No man shall bathe in dirty water or in an amount too shallow to cover a man. He shall not purify himself with water contained in a vessel" (from chapter 10).

"No man entering the house of worship shall come unclean and in need of washing" (from chapter 11).
Early Rabbinic BAPTISM OF INITIATION:
In rabbinic and earlier forms of Judaism, baptism (along with male circumcision and sacrificial offerings) was a requirement for full conversion. The dating of this practice is somewhat obscure, but it postdates the Old Testament and predates the Mishnah. The Soncino Talmud states: "As your forefathers entered into the Covenant only by circumcision, immersion and the sprinkling of the blood, so shall they [the proselytes] enter the Covenant only by circumcision, immersion and the sprinkling of the blood" (Keritot 9a).
Later Rabbinic BAPTISM OF PURIFICATION:
After the destruction of the Temple in 70 A.D., the biblical purification laws (see above, OLD TESTAMENT ) were confined to the purification of the niddah, the ritually unclean woman discussed in such passages as Leviticus 12:1-8 and 15:19-24. The Jewish mikveh (immersion or t'vilah in a ritual bath) embraces both of the categories of purification and initiation and is practiced among Orthodox Jews to this day.

New Testament Period

BAPTISM OF REPENTANCE:
John the Baptist used baptism to symbolize an individual's repentance or return to the covenant. He demanded that an inward conversion precede the outward sign and be followed by evidence of a changed John the Baptist life.

"John did baptize in the wilderness, and preach the baptism of repentance for the remission of sins" (Mark 1:4; see also Matthew 3:11 and Luke 3:3).
Sibylline Oracles (a genre of literature found in the ancient world among Greeks, Jews and pagans, typically predicting disaster and misfortune)

BAPTISM OF REPENTANCE:
In this general time period, others also practiced a baptism of repentance. A portion of the Sibylline Oracles dated ca. 80 A.D.contains this passage:

"Ah, wretched mortals, change these things, and do not lead the great God to all sorts of anger, but abandon daggers and groanings, murders and outrages, and wash your whole bodies in perennial rivers. Stretch out your hands to heaven and ask forgiveness for your previous deeds" (4:165).

John's baptism differed distinctly because of his specific reference to the One yet to come who would baptize with the Holy Spirit and with fire (Matthew 3:11).
Christian Rite of Baptism

BAPTISM OF IDENTIFICATION:
Christian baptism is rich in symbolism and significance. It is symbolic of entering into Jesus' death and resurrection:

"Know ye not that, as many of us as were baptized into Jesus Christ were baptized into his death? Therefore, we are buried with him by baptism into death, that as Christ was raised up from the dead... we also should walk in newness of life. For if we have been planted together in the likeness of his death, we shall be also in the likeness of his resurrection" (Romans 6:3-5).

It is symbolic of passing through judgment into salvation :

"For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh but made alive by the Spirit, by whom also he went and preached unto the spirits in prison, who at one time were disobedient... in the days of Noah, while the ark was preparing, in which few... were saved by water; the like figure unto which even baptism doth also now save us (not the putting away of the filth of the flesh, but the answer of a good conscience toward God), by the resurrection of Jesus Christ, who is gone into heaven ...." (1 Peter 3:18-22).
Spirit Baptism of Believers

BAPTISM OF APPLICATION:
"Then remembered I the word of the Lord, how he said, John indeed baptized with water; but ye shall be baptized with the Holy Spirit" (Acts 11:16). The work of Yeshua is applied not symbolically but in reality by the Holy Spirit to the believer.

Some aspects of the Spirit's work:

Initiation into a new life : "For by one Spirit were we all baptized into one body, whether we be Jews or Greeks, whether we be bond or free; and have been all made to drink into one Spirit" (1 Corinthians 12:13).

Cleansing : "Not by works of righteousness which we have done, but according to his mercy he saved us, by the washing of regeneration, and renewing of the Holy Spirit, which he shed on us abundantly through Jesus Christ, our Saviour" (Titus 3:5-6).

Identification with Jesus in his death and resurrection: Romans 6:3-5 (see above)--not symbolically but in reality.