AUSTIN, Texas (CNN) -- Amid heightened security, beaming supporters, and chants of 'shame' from dozens of black clad abortion-rights activists, Gov. Rick Perry signed Texas' controversial Fetal Pain bill into a law Thursday.

"In signing House Bill 2, we celebrate further the cementing of the culture of life which Texas is built upon...children do deserve the respect of simple recognition before their lives are cut tragically short," Perry said.

The law, considered some of the most restrictive abortion legislation in the nation, will ban abortions past 20 weeks of gestation, mandate abortion clinics upgrade facilities to become ambulatory surgical centers, tighten usage guidelines for the drug RU486, and require doctors who perform abortions to have admitting privileges at a hospital within 30 miles of the clinic at which they're providing abortion services.

For weeks, the sound of prayer and drum circles reverberated through the Statehouse rotunda as thousands of supporters and opponents of the bill descended on the capital building. The voices were loud, earnest, and often angry, and between the two sides there was little middle ground to be seen.

Inside a Statehouse auditorium, the signing of the bill quickly took on religious overtones with supporters often expressing approval with an 'Amen.' For anti-abortion activists like Marlene Salcher, Thursday's signing was an answer to her prayers.

"I believe that life begins at the beginning because God said he knew us in the womb and he knew us from birth," she said.

Salcher was onsite at the Statehouse during some of the most intense protests over the past weeks, often holding up a small doll in the likeness of a 20 week old fetus. When asked about how she felt about the women on the other side of the issue, she paused as she tried to put herself in their shoes.

"I pray for them, especially the young women," she said. "I feel like maybe they don't quite understand what it's like to have a child, or maybe they've been raped or had sex with someone outside of marriage and got pregnant and was told the lie that it was just a piece of tissue."

Lieutenant Gov. David Dewhurst acknowledged the determination of the bill's opponents,

"I understand that this has been a divisive issue and I believe this with all my heart...for those outside chanting, who may not agree with us, we love you just as much as we love those unborn babies," Dewhurst said. "We respect your right to free speech, as Texans we respect your toughness, but we made a commitment to pass this bill and we did."

Passage of the bill marks the beginning of more than a year of implementation. The twenty week ban will go into effect 91 days from the bill's signing, while enforcement for the rest of the bill begins in September 2014.

Abortion rights activists are expected to mount a challenge to the bill in court.

The bill originally failed to gain approval because of a Democratic filibuster led by state Sen. Wendy Davis. Perry called the legislature into a second special session to continue consideration of the bill.

The bill passed the state House and state Senate last week.