Middos, Chapter 2, Mishnah 3. This chapter walks us outward and then inward again through the concentric areas of the Har Habayit, each with its own degree of kedushah. Our mishnah stops at two of them: the soreg, a low wooden fence, and the cheil, the strip of ground lying between that fence and the walls of the courtyard. From there the mishnah turns into something like an architect's summary, listing the standard measurements of the Beit Hamikdash and, in each case, the one exception to the rule.
A word first about what these areas meant in practice. The cheil carried a kedushah of its own: a non-Jew who served idols could not set foot there, and neither could a Jew who had contracted tumat met, impurity from contact with a corpse. To mark off that zone, a wooden fence, the soreg, ran along its outer edge, dividing the cheil from the rest of the Temple Mount.
The Soreg
"Lifnim mimenu soreg gavoha asarah tefachim." Inside the wall of the Har Habayit stood the soreg, a wooden partition ten tefachim high. It encircled the courtyard walls on all four sides, set back a distance of ten amot from them. Picture the arrangement from the inside out: the Beit Hamikdash itself, then the courtyard walls, then the ten amot of the cheil, and then the soreg, holding back the general expanse of the Temple Mount.
"U'shelosh esreh peratzot hayu sham sheparetzum malchei Yavan." Thirteen breaches had once been made in that fence by the Greek kings. When they seized control of the Beit Hamikdash they had no regard for the halachot of kedushah, and they deliberately smashed openings so that idol worshippers could walk straight through into the cheil.
"Chazru u'gedarum v'gazru kenegdam shelosh esreh hishtachavayot." Once the Jewish people recovered the Temple Mount, they sealed every one of the thirteen gaps, and corresponding to them they instituted thirteen places of bowing. Whoever came onto the Har Habayit and passed one of the repaired spots would bow there and give thanks to Hashem for the defeat of the Greeks. The very places that had been marks of disgrace became stations of gratitude.
The Cheil and Its Steps
"Lifnim mimenu hacheil eser amot." Within the soreg lay the cheil, occupying those ten amot between the fence and the walls of the courtyard, on all four sides.
"U'shteim esreh ma'alot hayu sham." Twelve steps stood there, on the eastern side of the cheil. "Rum hama'alah chatzi amah v'shilchah chatzi amah": each step rose half an amah, and the tread on top of each step measured half an amah as well. These steps were the means of ascent at that point. From here the mishnah moves on to a series of general rules about the building.
Every Rule and Its Exception
"Kol hama'alot shehayu sham rum ma'alah chatzi amah v'shilchah chatzi amah, chutz mishel Ulam." Every flight of steps in the Beit Hamikdash was built to that same standard, a rise of half an amah and a tread of half an amah. The exception was the set of steps leading up to the Ulam, the entrance hall on the eastern side of the Heichal building, whose treads were longer than an amah.
"Kol hapetachim v'hashe'arim shehayu sham govhan esrim amah v'rochban eser amot, chutz mishel Ulam." All the doorways and gateways there shared one set of dimensions: twenty amot high and ten amot wide. Again the Ulam stood apart, its opening measuring forty amot in height and twenty in width.
"Kol hapetachim shehayu sham hayu lahen delatot, chutz mishel Ulam." Every doorway in the Mikdash was fitted with doors, with the single exception of the entrance to the Ulam, which had no doors at all and was closed off instead by a curtain.
"Kol hashe'arim shehayu sham hayu lahem shakofot." Every gateway had a shakof, a lintel, the horizontal beam resting on the two doorposts, "chutz misha'ar Tadi shehayu sham shetei avanim mutot zo al gav zo": except for Sha'ar Tadi, where instead of a flat lintel two stones leaned one against the other at an angle. Where all the other gates were squared off on top as we would expect, this one was crowned by a peak, the two stones forming a triangle above the opening.
The Gates of Gold and the Gate of Copper
"Kol hashe'arim shehayu sham nishtanu lihiyot zahav." When the Second Beit Hamikdash was built, the people could afford no more than copper plating for the doors of the gates. Later, as their circumstances improved, all those gates were upgraded and overlaid with gold, "chutz misha'ar Nikanor", except for Sha'ar Nikanor, "mipnei shena'asah bahen nes", because a miracle had occurred with its doors.
That miracle was recounted in perek aleph. The doors were being brought by sea, and when a storm threatened the ship one of them was thrown overboard. When the sailors moved to throw the second one as well, Nikanor refused to let it go, and the storm subsided; the door that had been cast into the water was recovered, and both reached the Beit Hamikdash. Those doors were therefore left in their original copper. Preserving the memory of what happened counted for more than the honor of a gold overlay.
"V'yeish omrim mipnei shenechushtan mazhiv." Others explain that there was simply no need to change them: they were fashioned from a rare and precious copper that gleamed with the luster of gold.