Billy Paul, the Philadelphia soul singer best known for "Me and Mrs. Jones," the sublime cheating song that is a peak experience from the classic Sound of Philadelphia era, died of cancer on Sunday at age 81. His obituary is here.

Is "Me and Mrs. Jones," which was written by Kenny Gamble, Leon Huff and Cary Gilbert and a #1 pop and R&B hit for Paul in 1972, the greatest sneaking around song of the '70s soul era? You know it is, though Luther Ingram's Stax hit "If Loving You Is Wrong (I Don't Want To Be Right)," also from 1972, comes in a close second.

Gamble and Huff released this statement on the passing of Paul on Sunday:

"We are very saddened to learn of the sudden death of our good friend and Philadelphia International Records recording artist Billy Paul. From the time we saw Billy performing live, and then signing him to our PIR/TSOP label, we immediately realized that we had discovered and launched one the most unique voices in the music industry. Billy's voice combined both Jazz, R&B and Soul vocals, making him one the great artists to come out of Philly and to be celebrated worldwide. Our proudest moment with Billy was the recording of the salacious smash 'Me and Mrs. Jones.' In our view, it is one of the greatest love songs ever recorded. Billy ...will forever have a special place in music history."

But there was more to Billy Paul, who was born Paul Williams, than "Me and Mrs. Jones." The North Philly native was a teenage ballad singer in the early 1950s, before later in the decade serving in the U.S. Army in Germany, where he was stationed with Elvis Presley and formed a band with Bing Crosby's son Gary.

He fronted jazz and soul combos in the '60s in Philadelphia and released Feelin' Good At The Cadillac Club on the Gamble label in 1968. After "Me and Mrs. Jones," for the album 360 Degrees of Billy Paul topped the charts, Philadelphia International followed the hit up with "Am I Black Enough For You?," one of the label's most confrontational, socially conscious releases, which was regarded warily by conservative radio programmers. It killed the "Mrs. Jones" momentum, but had an impact as an anthem of racial pride in the long run, and was sampled on the title cut to Philadelphia gangsta rap pioneer Schoolly D's 1989 album Am I Black Enough For You?

Paul's 1973 album War Of The Gods is a trippy six-song psychedelic soul experience that followed Isaac Hayes, Marvin Gaye and the Temptations' "Papa Was A Rolling Stone" into a mind expanding direction. It's ripe for rediscovery, and worth a look and listen for the album art alone.

Paul's 1975 album When Love Is New again caused controversy when his songs "Let's Make A Baby" was considered too risque for radio play. And in 1976, the avowed Beatles fan recorded a memorable cover of  Paul McCartney's "Let Em In," which he recast as a Civil Rights anthem. Check out those songs below.

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