Phil Robertson disrespected gay employees at A&E ... and THAT'S why he was sacked from "Duck Dynasty" ... sources connected with the network tell TMZ.
We're told A&E CEO Nancy Dubuc felt she could not in good conscience ask gay employees to kill themselves for a show when he disrespected them by calling them sinners.
Our sources say ... gay employees involved in the production -- and there are a number of them -- were outraged by Phil's comments to GQ and wanted Dubuc to give him the ax.
We're told Dubuc felt this way ... If Phil had made similar comments about African Americans or Jews ... there would have been a public outcry for his head. She felt it was just plain wrong not to have the same sense of indignation when the comments were directed at gays.
Our sources say GLAAD was heavily involved in lobbying the network to 86 Phil, and they had an impact.
As for TMZ's criticism that A&E knew full well what it was getting with Phil when they hired him ... as one source put it, "He just took it too far with GQ ... especially with the coarse language."
Our sources say A&E is adamant -- this has nothing to do with being "anti-religion." Fact is ... the network runs lots of religious programming, notably, Mark Burnett's "The Bible."
The CEO is paying the price. We're told she's been receiving death threats.