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ADEL, Iowa-Paul Ryan weighed in Wednesday on the Democrats' 2012 platform, which makes no reference to "God," calling the omission "rather peculiar."

"It's not in keeping with our founding documents, our founding vision, but I guess you would have to ask the Obama administration why they purged all this language from their platform," Ryan said on Fox News.

The word God is not mentioned in the U.S. Constitution. The word "Nature's God" appears once in the Declaration of Independence, alongside mention of the word "Creator."

The new platform refers to faith, saying it "has always been a central part of the American story." It also says the US was founded on the principle of religious freedom and the ability of people to worship as they please. It praises the work of faith-based organizations.

Read the U.S. Constitution

Republicans have sought to highlight the absence of the word God from Democrats' platform. "God" was mentioned once in Democrats' 2008 platform. The 2012 GOP platform mentions God 12 times. Democrats also left out two sentences from the platform draft that identified Jerusalem as the capital of Israel and a pledge to "isolate Hamas until it renounces terrorism."

Read more about Democrats' platform

As for leaving out the mention of Jerusalem as the capital of Israel, Ryan called it "tragic" because "this is one of the few issues where the Republican Party and the Democratic Party agreed."

Jerusalem is declared the capital of Israel in the RNC platform.

"To see this kind of language, this acknowledgement removed from their party platform is really kind of disappointing," Ryan said.

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At a rally here, Paul Ryan mentioned the DNC again, previewing Bill Clinton's speech to the Democratic National Convention this evening saying he thinks the former president will look back at the time he was in the White House rather than the "last four years."

"We are going to hear from President Clinton tonight in Charlotte," Ryan said in front of the courthouse here. "My guess is we will get a great rendition of how good things were in the 1990s, but we're not going to hear much about how things have been the last four years."

Ryan even mentioned some of Clinton's successes including welfare reform and accused President Obama of "rolling back welfare reform." He noted that Clinton worked across the aisle with Congress, while Obama is a "gusher of new spending and only demagoguery from those of us who have offered solutions."

"Under President Clinton, we got welfare reform," Ryan told a crowd of several hundred people. "Chuck Grassley, everybody else in Congress - we got welfare reform, which moved people from welfare to work to get people out of poverty. President Obama is rolling back welfare reform. President Clinton worked with Republicans in Congress to have a budget agreement, to cut spending."

Ryan's welfare attack has been widely debunked. Instead of "rolling back" the work requirement, the Obama administration is responding to requests from both Democratic and Republican governors to allow states to apply for a waiver to administer the work requirements in their states. The Romney campaign has used this as a line of attack, accusing the president of wanting to gut the work requirement.

The Obama campaign immediately responded, calling the attack a "lie."

"While the Congressman has proven his willingness to ignore the truth, even he should know that President Clinton has joined with every independent fact checker, news organization, and a Republican architect of welfare reform in calling the welfare attack blatantly false," Obama spokesperson Danny Kanner said in a statement.

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