Johann Sebastian Bach, in his position as composer and church organist, barely had time to enjoy the fruits of his written work in performance from one week to the next. Such was the nature of his liturgical assignments in the great houses of worship in Leipzig, Muhlhausen and Weimar, Germany, back in the early decades of the 18th century. Now, here is the amazing part of this chapter in his life: In total, he wrote more than 300 sacred cantatas of which almost 200 survive.

The National Philharmonic, led by music director and conductor Piotr Gajewski, will perform Bach's 140th cantata, one of his most beautiful works, this Saturday at the Music Center at Strathmore. Entitled "Wachet Auf," or "Sleepers Awake," approximately 120 voices from the Philharmonic's Chorale will join the orchestra in what was originally composed as a wedding cantata.

"We will use as full an orchestra as there was in Bach's time," Gajewski noted. There will be a full complement of strings, three oboes, piccolo, horn and organ."

Soprano Rosa Lamoreaux, tenor Matthew Smith and bass Kevin Deas are the soloists in the piece.

National Philharmonic Orchestra and Chorale: Bach's Brandenburg Concertos Nos. 1 and 5
» Where: Strathmore, 5301 Tuckerman Lane, North Bethesda
» When: 8 p.m. Saturday; preconcert lecture at 6:45 p.m.
» Info: $28 to $81, children 7 to 17 free; 301-581-5100;

The evening's program begins with Bach's Brandenburg Concertos, Nos. 1 and 5.

"These concertos are very unique for Bach's time," Gajewski explained. "They are written for different groupings of instruments. In particular, the first one is written for two horns, oboes and violin, [and] the fifth is for violin, flute and harpsichord. This is an early example of a very strong role for the harpsichord -- there is an extended cadenza in the first movement."

Other musicians joining the performance are harpsichordist William Neil, flutist David Whiteside, oboists Mark Hill, Kathy Ceasar-Spall and Fatma Daglar, as well as horn players Michael Hall and Mark Wakefield.

Bach's baroque masterpieces continue to have a prominent place in 21st-century classical performance.

"It's especially coming back in vogue to play Bach's [works] on symphony orchestra programs," Gajewski said. "We've been doing it for years, and it works very well!"