Defilement of the Sanctuary by the Blood of Forgiven sins. 
The sanctuary was defiled also by the sins which were confessed and atoned for through the daily sacrificial system. These sins were symbolically transferred into the sanctuary through the manipulation of the sacrificial blood, or in some cases through the eating by the priest of the flesh of the sacrifice. The blood of the sacrifices offered for penitent sinners defiled the sanctuary, because it was used to symbolically carry their sins into the sanctuary where they were kept until the Day of Atonment. The sacrificial system operated on the principle of substitutional interchange (cf. Is 53:10-11). 
On the one hand the purity of the sacrificial animal (Lev 4:3, 23; Num 19:2) was transmitted symbolically through the blood rites to the impure, sinful person. On the other hand, the sins of the penitent sinners were transmitted to innocent animals by confession and the laying on of hands on their heads. In turn the sins assumed by the animals were brought into the sanctuary through the manipulation of the blood or the eating of the flesh by the priest. The result was that the sanctuary was defiled by the sins deposited there and needed to be cleansed on the Day of Atonment.89 
The function of blood in the Old Testament sacrificial system was equivocal, since it was both a cleansing and defiling agent. The blood of sacrifices purified penitent sinners defiled by sin, yet the same blood defiled the sanctuary because it symbolically carried there the sins which had been atoned for. The daily accumulation of sins deposited in the sanctuary necessitated its annual cleansing of the sanctuary on the Day of Atonment.
"During the year," as Alberto Treiyer points out. "the blood was deposited in the place which God had sanctified with His glory–His sanctuary (Ex 29:43). In this manner sin was transferred to the sanctuary complex and contaminated it. At the end of the year, on the Day of Atonement, the paradox of the substitutional principle operated again, and the blood became the element for the purification of the sanctuary from all the sins which had contaminated it to that point. Then in the figurative ritual the sins were blotted out totally from Israel."10 This process of transference of sins into the sanctuary where they were symbolically kept until the Day of Atonment when they were disposed of in a final and permanent way, typifies an important aspect of the plan of salvation: the process leading to the ultimate eradication of sin and its effects.
Shortly we will address the question of why were sins deposited and kept in the sanctuary until the Day of Atonment, though they had been atoned for during the daily services. At this juncture we wish to consider briefly how sins were symbolically transferred to the sanctuary.
Function of the Sacrificial System. 
We already noted that sins were atoned for and transferred to the sanctuary through the sacrificial system. Such system was divinely established as a means to restore a relationship between God and man broken by sin. The sacrifice of an animal functioned as a substitution for the offender, by bearing the punishment of the person to be sacrificed (Ex 32:30; Is 53:6-10). Sin offerings served the double function of cleansing penitent sinners of their sins, and carrying their contamination to the sanctuary. The value of animal sacrifice in the Old Testament lie in the fact that they were prophetic, pointing to "the lamb of God, who takes away the sins of the world" (John 1:29). Hebrews explains that "it is impossible that the blood of bulls and goats should take away sins" (Heb 10:4).
The process of transferring sin from the offender to the sanctuary involved first of all the laying of hands upon the head of the victim and making confession of sin (Lev 1:4; 4:4, 24, 29, 33; Lev :5-6). "The laying on of hands on the head of the victim symbolizes, together with the confession of sins, a transfer of sin from the offerer to the victim. The victim ‘carries’ the offerer’s sin, and is his substitute, as the sacrifice takes the place of the sacrificer."10
The rite of the laying on of hands fulfilled a double function. On the one hand it removed the sin from the guilty person or group and made them clean. On the other hand it transferred the sin of the offerer to the sacrificial animal who in turn carried it to the sanctuary. The latter process needs further clarification.
The Rite of Blood Manipulation. 
Sins were symbolically carried into the sanctuary through the rite of blood manipulation or through the rite of eating sacrificial flesh by the priests. Through these rites the sanctuary (that is, God) assumed accountability for the sins of repentant sinners who had confessed their sins and placed them upon the Lord through the mediation of the priests.
The rite of blood manipulation is described in Leviticus 4:1-21. The sin offerings for an individual (Lev 4:1), "the anointed priest" (Lev 4:3), and the whole Israelite community (Lev 4:13-21), required the slaying of a "bull without defect" (Lev 4:3) after the laying on of hands. Then the priest handled the blood according to this specified ritual: "And the anointed priest shall take some of the blood of the bull and bring it to the tent of meeting; and the priest shall dip his finger in the blood and sprinkle part of the blood seven times before the Lord in front of the veil of the sanctuary. And the priest shall put some of the blood on the horns of the altar of fragrant incense before the Lord which is in the tent of meeting, and the rest of the blood of the bull he shall pour out at the base of the altar of burnt offering which is at the door of the tent of meeting" (Lev 4:5-7).
The blood that was brought into the Holy Place for sprinkling against the veil and upon the horns of the altar of incense, served to symbolically transfer into the sanctuary the sins which had been atoned for. There the sins remained until the Day of Atonment, when the sanctuary was cleansed of the accumulated sins of the people. This blood ritual of the daily services was not "a ritual detergent for purging the sanctuary,"11 because it is explicitly stated that "the priest shall make atonment for them [the people]" (Lev 4:20), and not for the sanctuary. By contrast, it is explicitly stated that on the Day of Atonment the blood ritual served to cleanse the sanctuary (Lev 16:16) as well as the altar of burnt offerings (Lev 16:18-19). 
The Rite of Eating Sacrificial Flesh.
 A different blood ritual was used in the case of a sin offering for a leader (Lev 4:22-26) and the common Israelite (Lev 4:27-35). In these instances the blood of the sin offering was not brought inside the sanctuary for sprinkling against the veil and upon the altar of incense (Lev 4:25, 30), but was sprinkled only on the altar of burnt offerings located in the court. "The priest shall take some of the blood of the sin offering with his finger and put it on the horns of the altar of burnt offering, and pour the rest of its blood at the base of the altar of burnt offering" (Lev 4:25). In this case the transferance of sin occurred by the eating of the flesh by the priest in the sanctuary.
Leviticus 10:17-18 suggests that when the blood of a sacrifice was not brought into the sanctuary, the priest had to eat some of its flesh in the sanctuary. Moses inquired of Aaron and his sons, saying: "Why have you not eaten the sin offering in the place of the sanctuary, since it is a thing most holy and has been given to you that you may bear the iniquity of the congregation, to make atonment for them before the Lord? Behold, its blood was not brought into the inner part of the sanctuary. You certainly ought to have eaten it in the sanctuary, as I commanded" (Lev 10:17-18).
The reference to the earlier command seems to go back to the instruction given in Leviticus 6:26, "The priest who offers it for sin shall eat it; in a holy place it shall be eaten, in the court of the tent of meeting." The purpose of the eating rite is explicit, "[It] has been given to you that you may bear the iniquity of the congregation, to make atonment for them before the Lord" (Lev 10:17). By eating the sacrificial flesh the priest became the carrier of the sin which had been symbolically transferred from the sinner to the sacrificial victim. The Lord stated: "You shall bear iniquity in connection with the sanctuary" (Num 18:1). It must be remembered that the priesthood was an integral part of the sanctuary. Consequently, whatever affected the priesthood affected the sanctuary also. However, since the priests could not atone for sin with their own life, they needed to bring a sin offering that provided for the transferance of sin to the victim whose blood was then sprinkled in the sanctuary (Lev 4:6). 
Summing up, all repented and confessed sins were transferred to an innocent victim by the laying on of hands. Through the sacrificial rites the guilty sinners were forgiven and cleansed, but their sins were not nullified. The sins borne by the sacrificial victim were transferred to the sanctuary either through the ritual of the blood sprinkling in the Holy Place or through the eating of the sacrificial flesh by the priest in the sanctuary complex..