A Shabbat addition: Good things are given additions before and after. But bad things remain as they are, meaning no additions are attached to them, and we choose the least bad.
Since Shabbat is a good thing, there are additions to Shabbat before it and after it. What is good about Shabbat? The writing says, “It is good to thank the Lord.” If a person can thank the Creator, this is called Shabbat. Accordingly, if one can thank the Creator in the middle of the week, that person is in a state of Shabbat, as our sages said, “A wise disciple is regarded as Shabbat.” That is, if he can thank the Creator, this is called “the state of Shabbat.”