Exodus 25-31, from the hand of the Priestly writer, is a detailed description of the components of the Tabernacle and all of its equipment and how they are to be constructed, which Moses receives from Yahweh while on Sinai.
Likewise, Exodus 35-40 is a detailed account of the construction of the Tabernacle and all of its components per its descriptions. There are a few contradictions in these Priestly passages, but more apparent are the contradictions that Exodus 25-31 and 35-40 create when added to the JE material in Exodus 32-24—which we will shortly look at.
Today’s contradiction has to do with the poles that are constructed to carry the Ark. Since all of the Tabernacles components: the Ark, Table, Menorah, Altar, etc, were deemed holy, i.e., untouchable by anyone but the Aaronid priesthood, they were carried and transported by poles. This was the job of the Levites. But the Levites themselves could not touch the holy items lest they die. Only an Aaronid priest, since he has been made holy himself, can touch these items. It is therefore the duty of the Aaronid priests to wrap these components in cloth and place their poles on them so that they may be carried, with the poles, by the Levites. This is outlined in Numbers 4.
Thus, with respect to the Ark:
And Aaron and his sons… shall put a cover of leather and shall spread a fabric all of blue above the Ark and put in its poles. (Num 4:5-6)
The problem is that Exodus 25:15 had Yahweh declare that the poles shall not be removed from the Ark’s rings. Furthermore, 1 Kings 8:6-8 implies that the Ark with its poles were carried into the Temple and there it remained with its poles intact, per the instructions given at Exodus 25:15!