At the time of the construction and completion of the first Bais HaMikdash, King Shlomo still had the original aron which Betzalel had built in the desert. Attached to the cover of the Aron was the two solid-golden Keruvim (10 tefachim or approximately forty inches high).
The plans for the Bais HaMikdash which Shlomo received from his father Dovid included two additional Keruvim to be made from wood and plated with gold. Each was 10 amos high (approximately 15-20 feet). They were placed on the floor in front of the aron, one to the right and one to the left. The width of these Keruvim with their outstretched wings took up the entire width of the haichel (20 amos).
The (two) Keruvim stood miraculously - "V'Chamesh Amos Kenaf ha'Keruv ha'Echas v'Chamesh Amos Kenaf ha'Keruv ha'Shenis..." (They stood next to each other, and the total span of all four wings was 20 amos, i.e. the entire length of the Kodesh ha'Kodoshim. We conclude that their bodies (in between the wings) did not occupy space!)
Side note: Can not ask that the vessels of the Bais HaMikdash use a smaller size of amah than the standard used to measure other sizes in the Bais HaMikdash, since these Keruvim were connected to the ground and thus, not vessels.
Six Chachamim offer objections to the concept that a miracle occurred with the Keruvim
Objection #1 (Abaye): Perhaps (there was no miracle) the wings of each Keruv touched each other, and the bodies were underneath, like chickens!
The wings of chickens meet in the back. Thus, according to this objection the wings’ span would occupy the full 20 amos and the body would overlap the space that included the wings.
Objection #2 (Rava): Perhaps they did not stand next to each other!
Rashbam says the Keruvim were not in one line and thus, their width overlapped.
Rabeinu Gershon says the Keruvim’s wings were not parallel to the ground, but at an angle.
Objection #3 (Rav Acha bar Yakov): (Even if they stood next to each other,) perhaps they were on a diagonal!
Rashbam says the Keruvim were placed diagonally which allows greater length of about 28 amos for the 20 amos of wings and also for the bodies.
Ritva objects to this explanation since the verses say that the Keruvim faced the Heichel. Therefore, he offers that the explanation that the wings of the Keruvim were at a diagonal.
Rabeinu Gershon offers a similar explanation that the diagonal of the wings was the inner wings.
Maharasha explains differently that the Keruvim were at a diagonal to the room and were at opposite angles to each other.
Objection #4 (Rav Huna brei d'Rav Yehoshua): Perhaps the Kodesh ha'Kodoshim is 20 by 20 at the bottom, but it is wider on top!
This object did not need a miracle to occur, since the room itself enabled the larger wingspan. The room measured 20 X 20 at the floor, but was vertical walls bulged allowing greater room for the wings, including the width of the bodies.
Objection #5 (Rav Papa): Perhaps the wings were bent!
Objection #6 (Rav Ashi): Perhaps the wings overlapped each other!
Question: What was the (normal) position of the Keruvim?
Answer #1 (R. Yochanan or R. Elazar): Each faced the other.
Answer #2 (the other of R. Yochanan and R. Elazar): Each faced the walls of the Kodesh ha'Kodoshim.
Question (against the first opinion): "U'Fneihem la'Bayis"!
Answer: When Yisrael does HaShem's will, they face each other; when we do not, they face the walls.
Question (against the second opinion): "U'Fneihem Ish El Achiv"!
Answer: They face each other somewhat, and also face the walls somewhat. (Beraisa - Unkelos): "Keruvim Shnayim Ma'ase Tza'atzu'im" - (their faces) looked like children leaving their Rebbi, i.e., looking slightly to the side.
