A Dallas lawmaker wants to change Texas' definition of marriage.

As it stands now, the state of Texas defines marriage as a union between a man and a woman. But state Rep. Rafael Anchia wants to allow same-sex couples to marry or enter civil unions.

"My constituents include many couples and families who are negatively impacted by the current constitutional restrictions," he said in a statement. "It is time we revisit this issue; it is time we treat all Texans with dignity and respect."

The measure co-authored by state Rep. Garnet Coleman would move to repeal the provision in the state constitution that defines marriage as a union between a man and woman.

But a Dallas pastor disagrees with the bill.

The Rev. Dr. Robert Jeffress, pastor of Dallas First Baptist, says the legal definition of marriage in Texas is fine the way it is.

"Jesus defined marriage in Matthew 19. He said marriage is a between one man and one woman in a lifetime relationship. And anytime society tries to redefine what God has designed, there is always going to be chaos," Jeffress said. "The problem is, when you redefine marriage and expand the definition of marriage, you cheapen what is traditional marriage and you give people a disincentive for getting married."

Anchia points to changing opinions on gay marriage, even citing a Texas Tribune poll that showed that more than 30 percent of Texans support civil unions between same-sex couples.

But Jeffress said public opinion can be wrong.

"I do believe opinions have changed, but public opinion is not always the best arbiter of what is right and wrong," he said. "After all, there was a time in history when the majority of people in our country said slavery was right, but that didn't make it right."

Anchia admits that the measure faces an uphill battle. At worst, it raises consciousness on the issue, he said. At best, it will go to the vote of the people.

More: House Joint Resolution 77