Barack Obama accepting the Profiles in Courage Award at the John F. Kennedy Library in Boston on Sunday. MSNBC Barack Obama on Sunday urged Congress not to repeal the Affordable Care Act, marking his most significant foray into the healthcare debate since leaving office in January.

Obama was accepting the Profiles in Courage Award at the John F. Kennedy Presidential Library and Museum in Boston when his speech turned to healthcare reform. Without mentioning the ACA by name, or noting that House Republicans voted to repeal and replace it Thursday, the former president commended members of Congress who helped pass his healthcare bill in 2009, costing many their political careers.

"It is my fervent hope and the hope of millions that regardless of party, such courage is still possible," Obama said. "That today's members of Congress, regardless of party, are willing to look at the facts and speak the truth, even when it contradicts party positions."

He then encouraged lawmakers not to replace his signature legislative achievement with the American Health Care Act, which some analysts predict would disproportionately hurt the poor and sick.

"I hope that current members of Congress recall that it actually doesn't take a lot of courage to aid those who are already powerful, already comfortable, already influential, but it does require some courage to champion the vulnerable, and the sick, and the infirm — those who often have no access to the corridors of power," he said.

"I hope they understand that courage means not simply doing what is politically expedient, but doing what they believe deep in their hearts is right," he added.

The American Health Care Act now moves to the Senate, where it faces an uncertain future. A group of Republican senators has begun drafting legislation that is set to look different from the House-passed legislation.

Watch part of Obama's speech below: