"Highwire"

I listened to Argent's Circus yester-day to mark the fiftieth anniversary of its U.K. release, and for the first time, I noticed an allusion in "Highwire."  About halfway through the song, there's the line "With amazing grace and sweet sensation captured by the high flier," which seems to contain a nod to the spiritual "Amazing Grace" ("Amazing grace - how sweet the sound / That saved a wretch like me!").  I find some of the singing on Circus hard to understand; otherwise, I'm sure I would have discovered this reference earlier.