Mark Morris Dance Group’s weekend run at the Kennedy Center offers both temporal bliss and a textbook study in American arts funding. Thanks to a generous investment by the Kennedy Center, the company will perform “L’Allegro, il Penseroso ed il Moderato,” a 1988 evening-length work set to an oratorio by Handel, with live accompaniment by the Washington Bach Consort. The dance company has deep ties to the D.C. area, performing here annually and featuring local dancers like Rita Donahue, Spencer Ramirez, William Smith III, and Elisa Clark. Yet it’s been 13 years since Morris last performed “L’Allegro” here. Whether Morris could even create another similarly large-scale work is doubtful. The piece debuted in Brussels, when Morris was essentially the in-house choreographer at Belgium’s national opera. He had substantial resources at his disposal then; now, he needs help to stage “L’Allegro” in the States. The choreographer has long championed live music, and musicians love him for it. (Yo-Yo Ma often plays chamber music in the pit when Morris debuts a new work in New York.) But that also means that “L’Allegro” can only be performed when a venue is willing to foot the bill for a few extra dancers, four singers, and a full orchestra. Say what you will about the Kennedy Center’s conservative approach to dance; this weekend, the cultural edifice deserves praise for putting its money behind a modern masterpiece. Mark Morris Dance Group performs at 7:30 p.m. tonight and Saturday at the Kennedy Center Opera House. $19-$69. kennedy-center.org. (202) 467-4600. (Rebecca J. Ritzel)

MUSIC

Friday: Jeff Mangum is sold out, but do go to tonight’s benefit for DJ Jonathan Toubin, the New York party starter who was gravely injured in a freak accident last month. The Comet Ping Pong show features well-pedigreed local bands Chain and the Gang, Deathfix, and Cane and the Sticks. 10 p.m. $10. Other good options include the Lightfoot record release at Black Cat, and much much more.

Saturday: The 21st century is a great time for 18th century music: We live in a moment of uncanny interest in baroque and Renaissance fare. Classical music’s “historically informed” movement, which maintains that antiquated music is best performed on antiquated instruments, has moved from the fringe to the mainstream. But it wasn’t always like this. In Bach’s day, most composers’ works weren’t deemed sacrosanct. Parisian and Viennese audiences didn’t care to hear last year’s symphonies, and orchestra directors routinely rewrote now-classic operas to keep them fresh. One of D.C.’s leading period ensembles, the Bach Sinfonia, respects “old” music in a way that its original audiences did not. For tonight’s “Bach Project,” flutists Stephen Schultz and Kathie Stewart will play the music of two Bach generations, as well as Telemann, Hotteterre, Quantz, and Haydn, accompanied by violoncello and gamba. It’s a performance that stands to heap more reverence on these composers than they ever received in life. The Bach Sinfonia performs at 8 p.m. at Montgomery College Cultural Arts Center in Silver Spring. Pre-concert discussion led by director Daniel Abraham at 7:15 p.m. $15-$30.