Read Lev 7:11-21; 28-36; Ex 29:26-28; I Sam 1:4,5
The Peace offering has associated with it: the wave offering and the heave offering. There were three types of peace offerings: thanksgiving, vow, and voluntary (free will).
The chief feature of the peace offering was the festive meal, shared by G-d, the priests, and the offerer. This is the only offering in which the offerer ate part of the offering. The peace offering was always offered last when offered with other offerings. It could also be offered by itself. It was offered to express a feeling of peace after a person experienced pardon, and had consecrated their life to G-d.
It was not offered by someone seeking peace, but was offered by someone in a state of peace. The peace offering as always laid on the burnt offering, teaching that only a consecrated life can lead to peace. This typified Yeshua in that it portrayed His death by which peace, reconciliation, and communion with G-d are possible.
The portions of the offering given to the priests were called the wave-breast and the heave-shoulder (thigh). The wave-breast was presented to the L-rd in a side-to-side swinging motion. The heave-shoulder (thigh) was moved up and down during its presentation. The presentation movements were to indicate the offerer's consecration to G-d, although the portions were not burned on the altar.
The portions for G-d were the rump, and all the fat that covers the entrails and the lobe of the liver, and the two kidneys and the fat that is on them where burned on the brazen alter.
The rest of the meat was for the offerer and His family. (I Sam 1:4,5)
Unleavened cakes, unleavened wafers, or blended flour cakes were offered along with leavened bread.
The offerer ate the leaven bread (remember leaven symbolizes sin). The priests, as G-d's representatives, ate the unleavened bread.
If the peace offering was for thanksgiving, the offerer's portion had to be eaten that day only. If the peace offering was for a vow type, or was voluntary (free-will) type it was to be eaten that day and could also be finished off the next day.
The thanksgiving offering was offered in retrospect for G-d's "past" goodness, in forgiveness for sin, and in protection from enemies or natural afflictions. (Examples: Psalms 107:19-22 and Psalms 116:9-17)
The vow offerings were offered only after certain conditions of a previous vow were fulfilled. A vow usually accompanied a prayer during times of sickness or distress. The vow itself was not made in hopes of enticing G-d to answer a prayer, but if the needs were met, the vow offering would be given in thanksgiving. The offerer could vow anything he owned, such as persons, animals, houses, or lands. These things were then to be used in the service of G-d. Although vows were made on a voluntary basis, once vowed, the person was obligated to complete the pledge, unless abrogated legally as stated in Numbers 30.
Eccl 5:4-5 "When you make a vow to G-d, do not be late in paying it, for He takes no delight in fools. Pay what you vow! It is better that you should not vow than that you should vow and not pay."
See also: Deut 23:21-23
If a person was vowed, he was redeemed. Vowing a person was actually an act of vowing a given amount of silver, which was given to a priest. The amount of silver for a vowed person was set according to age:
1 month to 5 year old - males; 5 shekels - females; 3 shekels
5 years to 20 years old - males; 20 shekels - females; 10 shekels
20 years old to 60 years old - males 50 shekels - females; 30 shekels
60 years old and above - males 15 shekels - females; 10 shekels
Animals, houses, and lands could also be redeemed at their estimated value, plus 1/5.
(See Lev 27)
The nature of the voluntary (free-will) offering is that of spontaneous thankfulness. Note Stunted or deformed animals were allowed for voluntary offerings. (Lev 22:23)