TITIAN IS COMING! Titian is coming! Titian opens Sunday at the National Gallery of Art! There's never been a Titian retrospective in this country before! There won't be another in our lifetimes! Come on down to the West Building! Hurry!

Sorry. But you'll go crazy too, when you see these paintings. In celebration of the 500th anniversary of his birth, some 70 Titians have been assembled from museums all over the world.

It's the second and last stop for the show, which ran for several months in Venice earlier this year. The National Gallery version is agreed to be better mounted than the Venice show and includes several major works not seen there.

And even the most assiduous, world-traveling Titian lover cannot have seen the equal of this exhibition, because many of the paintings have languished for centuries under layers of grime and excess varnish that coarsened the colors and blurred the brushwork of the genius whom many regard as the greatest painter the West has yet produced.

Before Titian even the greatest European masters were regarded as little more than talented tradesmen who painted portraits and scenes to order for the church, the state and the nobility. Since Titian, true artists have been recognized as among our best and our brightest, wellsprings of our culture. We no longer tell them what to do but try to learn from them.

National Gallery patrons have long enjoyed the finest collection of Titians in this country, but nothing can have prepared the visitor for the impact of this brilliantly designed show. The placement of each painting is perfect in relation to every other, and the maze of galleries has been arranged to accommodate the maximum number of viewers while providing quiet eddies where one may stand unjostled to study a particular work.

And what works! Here are the surviving three of the four ceiling paintings Titian executed. Here is the newly cleaned "Portrait of Francesco Maria della Rovere," revealing for the first time in centuries the exquisitely delicate reflections in his gleaming black armor. Here is the towering 1530 "Annunciation," long regarded as largely done by others, but now showing Titian's unmistakable brushwork.

While the Venice show was arranged chronologically, this one is thematic, with a few groupings of the earliest and latest works that serve to show that the young Titian was father of the old master: In his early twenties Titian was producing some of the most searching -- even searing -- portraits ever painted.

Titian learned something new about painting every day for more than 70 years, but all the greatness was there from the beginning; he didn't get better, he just did things differently from time to time. Toward the end (he died of the plague at age 86), Titian explored impressionism and seemed to be headed toward abstract expressionism. Some scholars have regarded the late canvases as unfinished, a hypothesis that seems unlikely to survive the revealing restoration of these works.

But, as the National Gallery's David Alan Brown says, Titian is not an artist who can be usefully discussed in the abstract. Great show! Great show! Get going!

TITIAN, PRINCE OF PAINTERS -- Sunday through Jan. 27 in the West Building, National Gallery of Art. Open 10 to 5:30 Monday through Saturday and 11 to 6:30 Sundays. Metro: Archives.