Actually, we can be positive that our seventh day is the same day Jesus observed when He was here on Earth - the day He kept every week as the Sabbath. (See Luke 4:16.) The days of the week have never been confused. Here's why some people ask this question ...

Before 1582, the world went by the Julian calendar, named for the Roman Emperor Julius Caesar, who implemented it in 46 BC. The Julian calendar had calculated that it takes the earth 365-¼ days to orbit the sun. However, it actually takes about eleven minutes less than that. Those eleven minutes accumulated each year until, by 1582, the calendar was 10 days out of harmony with the solar system.

On October ...

Here is the Old Testament text from which this common question arises: "The seventh day is the Sabbath of the LORD your God. In it you shall do no work: you, nor your son, nor your daughter, nor your male servant, nor your female servant, nor your ox, nor your donkey, nor any of your cattle, nor your stranger who is within your gates, that your male servant and your female servant may rest as well as you. And remember that you were a slave in the land of Egypt, and the LORD your God brought you out from there by a mighty hand and an outstretched arm; therefore the LORD your God commanded you to keep the Sabbath day" (Deuteronomy 5:14, 15).

The key to understanding this passage as it relates to Sabbath keeping ...

'Thus the heavens and the earth, and all the host of them, were finished. And on the seventh day God ended His work which He had done, and He rested on the seventh day from all His work which He had done. Then God blessed the seventh day and sanctified it, because in it He rested from all His work which God had created and made' (Genesis 2:1-3).

According to this Scripture
1. The time when God made the Sabbath was at the end of Creation week.

2. The way in which God made the Sabbath was by taking a day - the seventh day - and resting on it, blessing it, and sanctifying it.

3. The material out of which He made the Sabbath was ...