Leviticus 16:34

Leviticus 16:29-34 
“This shall be a permanent statute for you: in the seventh month, on the tenth day of the month, you shall humble your souls and not do any work, whether the native, or the alien who sojourns among you; for it is on this day that atonement shall be made for you to cleanse you; you will be clean from all your sins before the LORD. It is to be a sabbath of solemn rest for you, that you may humble your souls; it is a permanent statute. So the priest who is anointed and ordained to serve as priest in his father’s place shall make atonement: he shall thus put on the linen garments, the holy garments, and make atonement for the holy sanctuary, and he shall make atonement for the tent of meeting and for the altar. He shall also make atonement for the priests and for all the people of the assembly. Now you shall have this as a permanent statute, to make atonement for the sons of Israel for all their sins once every year.” And just as the LORD had commanded Moses, so he did.

From the Calvinist perspective, the Old Testament sacrifices were only offered for those who believe, rather than being offered for all Israel.

Dave Hunt: ...the Levitical sacrifices were for all Israelites, though most rebelled. That only those who believed were saved does not mean salvation was only offered to them.” (Debating Calvinism, p.384)

A.M. Mallet: “There is a place in the scriptures I turn to when challenged by those of the limited atonement view. It is a picture and type of what Christ would do once and for all at Calvary. In the Old Testament, Israel was instructed to observe a particular day and a statute kept ever more and still kept to this day through Christ’s fulfilled sacrifice. The High Priest offered a sacrifice to the LORD on the day of Atonement or Yom Kippur for the benefit of every soul within the borders of Israel including its strangers, the faithful and yes, those unfaithful. The sacrifice, being a picture of what Christ would do, presents Israel as a type of the world with all sorts of men within itself yet only a remnant truly known of the LORD as saints. There is nothing unlimited in this atonement except its efficacy through faith. This is a lesson I can only wish our Calvinist brethren would take to heart.” (An Atonement For All)