This portion closes (Bamidbar/Numbers 7:89) with a note about God speaking to Moses from between the Cherubim on the cover of the Ark.
There are cherubim set up to block the entrance to Eden at Breishit/Genesis 3:24. We first learn of the cherubim on the Ark cover in the Exodus chapter 25. The Ark and its cover are mentioned again in First Kings (cf chapter 6), 1 Chronicles 13, 2 Chronicles (cf. chapter 5) and in Psalms 80:2.
Cherubim figure in Ezekiel’s vision (chapter 10).
Plaut (The Torah: A Modern Commentary) — has an interesting section (see portion Terumah, Exodus 25ish) on such ancient images and their possible meanings. See also Terumah.