Cabell "Cab" Calloway III (1907 – 1994) was an American jazz singer and bandleader. He was strongly associated with the Cotton Club in Harlem, New York City where he was a regular performer.
Calloway was a master of energetic scat singing and led one of the United States' most popular African American big bands from the start of the 1930s through the late 1940s.

«Порги и Бесс» ― опера Джорджа Гершвина в четырех актах и девяти картинах. Впервые поставленная в 1935 году, опера на первых порах пользовалась сдержанным успехом, но с 1950-х годов начала завоёвывать широкую известность в США, а затем и во всём мире. «Порги и Бесс» ― одна из вершин творчества композитора. Музыкальный материал, выбранный Гершвином для создания оперы, разнообразен и основан на джазовых и блюзовых мотивах, негритянском фольклоре, импровизации. В либретто использована имитация «неправильного» народного произношения.

It ain't necessarily so
It ain't necessarily so
De things dat yo' liable to read in de Bible
It ain't necessarily so

Li'l David was small but oh my
Li'l David was small but oh my
He fought big Goliath who lay down and dieth
Li'l David was small but oh my

Oh Jonah he lived in de whale
Oh Jonah he lived in de whale
For he made his home in dat fish's abdomen
Oh Jonah he lived in de whale

Li'l Moses was found in a stream
Li'l Moses was found in a stream
He floated on water 'til ole Pharaoh's daughter
She fished him she says from that stream 

It ain't necessarily so
It ain't necessarily so
Dey tell all you chillun de debble's a villain
But 'taint necessarily so

To get into Hebben don' snap for a sebben
Live clean, don' have no fault
Oh I takes de gospel whenever it's pos'ble
But wid a grain of salt

Methus'lah lived nine hundred years
Methus'lah lived nine hundred years
But who calls dat livin' when no gal'll give in
To no man what's nine hundred years

I'm preachin' dis sermon to show
It ain't nessa, ain't nessa
Ain't nessa, ain't nessa
It ain't necessarily so