In discussing how Moses appointed various people over the functioning and transport of the Tabernacle, the Torah refers to the Tabernacle for the first time as a “testimony.”
Second Innocence
אֵלֶּה פְקוּדֵי הַמִּשְׁכָּן מִשְׁכַּן הָעֵדֻת וגו': (שמות לח:כא)
These are the appointments over the Tabernacle. The Tabernacle was a testimony. Exodus 38:21

The Torah refers to the Tabernacle as a “testimony” because it testified that G‑d forgave the Jewish people for the sin of the Golden Calf.

Moreover, the Hebrew word for “testimony” (eidut) is related to the word that the Torah uses for the “jewelry” (edi) – i.e., the spiritual crowns – that the people received at the Giving of the Torah and had to remove after the incident of the Golden Calf. Thus, the Tabernacle is also called “the Tabernacle of the jewelry.” This indicates that the Tabernacle was also the means by which G‑d enabled the Jewish people to regain the spiritual heights and Divine consciousness that they attained when G‑d first gave them the Torah – before the sin of the Golden Calf.

Similarly, by constructing our inner, personal spiritual Tabernacle, we, too, can overcome any spiritual handicaps we may have accrued during our lives, thereby attaining something of the pristine Divine consciousness G‑d bestowed upon us when the Torah was first given.1