For nearly 2,000 years, the Temple of Dendur stood on the banks of the Nile, its curious carving and harmonious hieroglyphs illuminated by the sun so often worshipped in the Egyptian province of Lower Nubia.

In the years since its construction in 15 B.C., the temple, a small, almost personal-sized shrine with traditional inclined walls and flat roof, never was an important edifice. It was just another small act of piety and statesmanship that the Emperor Augustus, (working on theory that no ruler can have too many subjects or too many deities) found expedient to erect to the local gods across the Roman Empire.

The Nile itself, however, was growing. As dam after dam was constructed, Lower Nubia was turned periodically into a vast Nile sea. For as much as nine months of the year, the deep water and mud of the river sloshed over the temple, permeating its sandstone and wasting away its rich colors.

The Aswan Dam would have meant the disappearance forever of the tiny temple - but in 1965, help arrived. Teams of workers arrived, dismantled the structure and shipped it all to the United States.

Now the temple, safe at last, has risen again - in a $9.5-million room, big as a city block, designed for the Metropolitan Museum of Art by Kevin Roche and John Dinkloo.

Afer 13 years of negotiation and construction, the public will be invited to see the shrine in its New World setting on Sept. 27, following invitational showings which will include the citizens of New York City, who helped pay for the new home.

The 41-by-82-foot gateway and temple now sit in a great 200-by-120-foot glass-roofed room, all carefully humidified, air-conditioned, lighted and guarded. The 200-goot-long 72-foot-high wall of metal framed glass extends the length of the room, revealing the temple to the suprised occupants of cars coming out of Central Park and onto Fifth Avenue.

At night, the temple is brilliantly lighted, and mirrored in a 32-by-102-foot reflecting pond that conjures up visions of the Nile and home.

Nubia, from the First to the Second Cataract of the Nile, stood as a buffer zone between Egypt and the Kush kingdom of the Sudan about 15 B.C. by this time Augustus had killed the son of Caesar and Cleopatra and had made himself ruler of Egypt and Nubia.

The first shrine on the spot, in the village of Dendur about 50 miles south now of Aswan, was a roughhewn structure cut out of the rock cliff. It was dedicated to two brothers, Pedesi and Pihor. The brothers were proboably minor princes. They were drowned, perhaps in a battle with the Eithiopians. The brothers' father was Kuper, a local dignitary appointed by Rome.

Herodotus, the historian, explained the ostensible reason for such a shrine: "When anyone, be he Egyptian or stranger, is known to have been carried off by a crocodile or drowned by the river itself, such a one must by all means be embalmed and tended as fairly as may be, and buried in a sacred coffin by the townsmen to the place where he is cast up . . . "

Actually, of course, it was a typically Roman effort to borrow legitimacy from the established religion.

According to Cyril Aldred, writing in the Metropolitan's Bulletin, the temple bears evidence of being hastily constructed, with errors here and there in the ritual depictions of heroes and gods mutually honoring each other.

To Christine Lilyquist, curator of Egyptian art at the Metropolitan, the ornamentation has a faintly Roman accent. "It's richer, lusher, than you'd expect of a purely Egyptian work."

As you enter the room, you see the great black watered reflecting pond intended to recall the Nile. A low wall of granite pretends to be the wharf. A rougher cut granite is set on either side of the gateway. The faithful would have come through the gateway to cleanse themselves of sin.

Virginia Burton, who supervised the reconstruction of the temple, says it was put back together by utilzing the original building method. "The Egyptians only used a thin slurry to help position the stones. The stones are not mortared together." The "battered" wall, as it is called, narrows as it goes up and is then topptd with the wide lintel.

Carved above the lintel is a winged disk, honoring the god Horus of Edfu, and protecting the building. The gateway and the temple are covered on most exterior faces by the "sunk relief," deeply incised carving. Originally, they were brilliantly painted.

One important picture on the gateway shows the Emperor Augustus giving a bag of eye paint to one of the brothers. Augustus is arrayed in the regalia of a pharaoh, complete with miniskirt, bare navel, beads and a bull's tail.

Most of the carvings show him offering wine and other sacrifices to either the brothers or to an assortment of gods including Osiris, Isis, Amun and the Nubian god Arsenuphis. Augustus was not taking his chances by leaving anyone out.

Once through the gateway, the pilgrim would have stood in a courtyard, originally walled, between the gateway and the temple. Visitors to the Metropolitan will not be so lucky; they will be banned from the entire platform that holds the gateway and temple.

The courtyard offers the best view of the composite capitals of the great columns. They are shaped of papyrus, and above them are the eyes of Horus. On the architrave is another winged disk. Inside the first room or Pronaos are more decorations including goddesses depicted as crowned cobras. Carved-into the thickness of the door-way is an inscription showing that the chapel was used as a Coptic church in 577 A.D.

The next room is a vestibule, once used for storing the ritual foods and furniture, and so it is plain, undecorated.

The final room is the sanctuary, where the supplicant comes face to fafe with the god of the place. Here the god is represented by a stela, a carved relief of Pedesi and Pihor offering gifts to Osiris and Isis. Aldred thinks it might once have been ornamented with gold and closed behind doors.

Standing here, listening to the silences of the stone, one could wish for the proper prayers to say and gifts to bring to propitiate such all-powerful beings.

The temple was given to the United States by the Egyptian government in gratitude for American assistance in saving the Nubian monuments from the Aswan Lake. Three others went to other countries who also helped.

A panel appointed by President Lyndon Johnson determined that the Metropolitan should have the physical possession, though the Smithsonian Institution entered a strong bid.

Arthur Rosenblatt, vice president for architecture and planning at the Metropolitan, said: "One of the principal reasons we got the temple, aside from our great Egyptian collections and scholars, was because we proposed to build a structure to protect it against the elements, yet one where it could be seen by the passer-by. The glass wall was our master stroke."

The wing also will house the new Sackler Gallery for Egyptian Art, a center for Far Eastern studies, and the Sackler Exhibition Hall, in which the enormously popular touring show of King Tut's treasures is scheduled to open in December.