He was a virtuoso performer on the organ and harpsichord and there is a story of a contest between Handel and Scarlatti in Rome, Italy on organ and harpsichord. Handel was judged superior on the organ while Scarlatti was judged superior on the harpsichord. He was born in the same year as both Scarlatti and J.S. Bach, but he never met Bach.
Handel has been highly esteemed by other composers. Mozart reportedly said of him, "Handel understands affect better than any of us. When he chooses, he strikes like a thunder bolt." And Beethoven was another admirer. "He was the master of us all, the greatest composer that ever lived. I would uncover my head and kneel before his tomb. Go to him and learn how to achieve great effects, by such simple means," Beethoven said of him.
He wrote in most forms of his time, but had his fame rest on Italian Opera and Oratorios. He wrote 42 Italian operas and when they fell out of favor he wrote Oratorios, of which his Messiah is the most well-known. During the intermissions of his Oratorios, Handel would conduct and play an organ concerto for orchestra and organ. He wrote 16 Oran Concertos, some of which have connections with specific Oratorios.
This concerto is taken from his Opus 7 set of six concertos. A contemporary critique of Handel's playing as written in 1776 by Sir John Hawkins in his book General History Of The Science And Practice Of Music:
"A fine and delicate touch, a volant finger, and a ready delivery of passages the most difficult, are the praise of inferior artists: they were not noticed in Handel, whose excellencies were of a far superior kind; and his amazing command of the instrument, the fullness of his harmony, the grandeur and dignity of his style, the copiousness of his imagination, and the fertility of his invention were qualities that absorbed every inferior attainment. When he gave a concerto, his method in general was to introduce it with a voluntary movement on the diapasons, which stole on the ear in a slow and solemn progression; the harmony close wrought, and as full as could possibly be expressed; the passages concatenated with stupendous art, the whole at the same time being perfectly intelligible, and carrying the appearance of great simplicity. This kind of prelude was succeeded by the concerto itself, which he executed with a degree of spirit and firmness that no one ever pretended to equal."
Handel's Organ Concerto #7, opus 7 No. 1 in B flat Major: