One of the biggest mistakes that millions of Christians make in our walk of faith is to believe that the feast days of Jewish holidays. They are the Holy Days of the Lord. God established these feasts and as believers in Yeshua it is our responsibility to understand them, to celebrate them within the adoption of our Christian worldview, and most importantly to study what they mean to us today.
Yom Kippur, the Day of Atonement, is the highest holy day of of the year. It was celebrated by the early church just as it was celebrated by Jews, though with an understanding that the sacrifices were replaced through the coming of our Messiah. It is the day that the Book of Life and the Book of the Dead are closed. It is the day that we are to humble ourselves in affliction through fasting and prayer.
1 Thessalonians 5:1-4
1 But of the times and the seasons, brethren, ye have no need that I write unto you.
2 For yourselves know perfectly that the day of the Lord so cometh as a thief in the night.
3 For when they shall say, Peace and safety; then sudden destruction cometh upon them, as travail upon a woman with child; and they shall not escape.
4 But ye, brethren, are not in darkness, that that day should overtake you as a thief.