Apple Inc. (NASDAQ:AAPL) CEO Tim Cook once again urged the United States Congress to pass the Employment Non-Discrimination Act (ENDA) is a message posted on Twitter Inc (NYSE:TWTR) today.

Apple CEO

Cook tweeted, “The House should mark the 50th anniversary of the Civil Rights Act by passing ENDA,” which was particularly addressed to the leadership of the House of Representatives including Speaker Boehner, Nancy Pelosi, and Whip Steny Hoyer.

His second tweet reads, “We shall overcome. Reflecting on the 50th anniversary of the Civil Rights Act. Much done but much left to do.”

Last year, Cook wrote an op-ed in the Wall Street Journal urging Congress to pass ENDA, which prohibits employers from discriminating applicants for employment based on gender or orientation.

Non-discrimination policy a matter of basic human dignity

Last year, Cook emphasized that Apple Inc. (NASDAQ:AAPL) is “committed to creating a safe and welcoming workplace for all employees, regardless of their race, gender, nationality or sexual orientation.”

He also pointed out that a non-discrimination policy is a matter of basic human dignity, and people perform the best in life if they know that they are valued based on their individuality.

Furthermore, Cook said that existing anti-discrimination policy of Apple Inc. (NASDAQ:AAPL) provides further legal protection than the existing federal law because the tech giant prohibits discrimination against gay, lesbian, bisexual and transgender employees.

“Protections that promote equality and diversity should not be conditional on someone’s sexual orientation…So long as the law remains silent on the workplace rights of gay and lesbian Americans, we as a nation are effectively consenting to discrimination against them. Congress should seize the opportunity to strike a blow against such intolerance by approving the Employment Nondiscrimination Act,” wrote Cook last year.

Senate approves ENDA

A strong bi-partisan majority in the Senate passed ENDA in November last year; however, the legislation was stalled in the House of Representatives, which is currently controlled by Republicans.

Speaker Boehner previously stated that he opposes discrimination of any kind, but he thinks the bill is unnecessary. He said, “I am opposed to discrimination of any kind — in the workplace and any place else. But I think this legislation — that I have dealt with as chairman of the Education Workforce Committee long before I was back in the leadership — is unnecessary and would provide a basis for frivolous lawsuits. People are already protected in the workplace. I am opposed to continuing this.”

Human Rights Campaign President Chad Griffin stated last year that ENDA will immediately pass in the House of Representatives if Speaker Boehner will release it for a vote in the lower house. “We firmly believe that if the House of Representatives were freed by Speaker John Boehner to vote its conscience, this bill could pass immediately. It’s unconscionable that any one person would stand in the way of this crucial piece of the civil rights puzzle,” said Griffin in a statement in November.