Did the Old Testament believers believe in atonement?

from the old testament

• The Mosaic Law God gave to the Israelites included animal sacrifices to atone temporarily for their sins throughout the year. Leviticus 4 discusses the sacrifices for unintentional sin that is brought to light. Leviticus 5 discusses the animal sacrifices required for those who sin with awareness of that sin.
• God's people also had an annual Day of Atonement in which the corporate sins of the nation were atoned for with two goats, one sacrified and one sent into the wilderness (Leviticus 16:8-10, 16:29-30, 23:27-28).
• Sacrifices had to be repeated throughout the year for ongoing sin (intentional and unintentional), and the Day of Atonement (now called Yom Kippur) was a yearly practice. Additionally, the priests had to atone for their own sins before atoning for the people's sins (Leviticus 16:6, 16:11).

from the new testament

• All the Old Testament sacrifices pointed to the ultimate, once-for-all atonement that the sinless Christ would carry out on the cross. The writer of Hebrews calls the Mosaic Law's temporary removal of sin merely "a shadow of the good things to come" (Hebrews 10:1). The limitations of that kind of atonement are evident: "it can never, by the same sacrifices that are continually offered every year, make perfect those who draw near. Otherwise, would they not have ceased to be offered, since the worshipers, having once been cleansed, would no longer have any consciousness of sins? But in these sacrifices there is a reminder of sins every year. For it is impossible for the blood of bulls and goats to take away sins" (Hebrews 10:1-4).
• When John the Baptist saw Jesus, he said, "Behold, the lamb of God who takes away the sin of the world" (John 1:29). John drew the parallel to the Old Testament atonement sacrifice ("Lamb"), but Christ's atonement for us was perfect and permanent (Hebrews 10:10-12).
• The apostle John describes Jesus our "advocate with the Father" and notes that "He is the propitiation for our sins, and not for ours only but also for the sins of the whole world" (1 John 2:1-2). Believers no longer need yearly animal sacrifice because Jesus has paid the sin debt in full for those who place their faith in Him.
• In the Old Testament sacrificial system, even the high priest had to make atonement for himself. But Christ as the perfect Son of God, needed no such atonement. He is the only qualified One to make permanent atonement for sins: "And every priest stands daily at his service, offering repeatedly the same sacrifices, which can never take away sins. But when Christ had offered for all time a single sacrifice for sins, he sat down at the right hand of God" (Hebrews 10:11-12).

implications for today

Cleaning can be satisfying. Once the dishes are washed, the beds made, the floor vacuumed and mopped, you can relax and enjoy a clean house—temporarily. Dishes get dirty by the next meal, the bed is unmade by night-time, and within a couple of days, the floor shows the effects of foot traffic. Maybe that's how the Israelites felt after going through the rites that atoned for their sin. They were temporarily "clean"—just until they sinned again (and, like us, they always sinned again).

Christ is the only one who can make us permanently clean because He covers us in His righteousness when we accept Him as Lord and Savior. We are washed in the blood of the Lamb and made righteous before God.

This should make us want to tell others about how they, too, can be made permanently clean through Christ. It doesn't take our efforts. No amount of elbow grease will accomplish it. Christ alone has fulfilled all that is required for our redemption.