The House and Senate this week voted overwhelmingly to provide back pay to about 800,000 federal workers who are going without paychecks because of the partial government shutdown.

But seven lawmakers - all House Republicans - opposed the measure. Those "no" votes came from Reps. Justin Amash (Mich.), Andy Biggs (Ariz.), Paul Gosar (Ariz.), Glen Grothman (Wis.), Thomas Massie (Ky.), Chip Roy (Texas) and Ted Yoho (Fla.).

President Trump on Thursday indicated he would sign the bill, leading to its passage by unanimous consent in the Senate later that day. On Friday, the House cleared the measure in a 411-7 vote.

In 2013, the House approved back pay for government workers in that year's shutdown in a 407-0 vote. The same measure received unanimous support in the Senate.

Most of the House Republicans who voted against Friday's measure are members of the conservative House Freedom Caucus, a group that frequently dissents on legislation that provides federal spending.

Roy issued a statement on Friday explaining his vote.

"There is zero question that we should pay federal workers. I do not, however, support putting federal spending on autopilot indefinitely or authorizing future pay irrespective of the circumstances," he said. "I would gladly have voted to pay federal employees at the end of the current lapse, but we should do so methodically and always ensure we are managing the budget wisely."

Government workers who are either furloughed or working without pay during the shutdown that's now in its 21st day missed their first paycheck on Friday, creating both financial hardship and uncertainty for employees. Many workers had their previous checks docked for one day of pay - Dec. 22, the first day of the shutdown - which coincided with the last day of a common federal pay period.

The legislation passed by Congress this week would also guarantee back pay in the event of a future shutdown.

Biggs said in a phone interview with The Hill on Friday that his main opposition to the legislation was the permanency of the back pay regarding other potential shutdowns.

"I would have voted for it, but because they made it permanent, so that we would not be as a legislative body considering that after every shutdown, you're actually moving to this thing where it becomes untenable," he said. "You just put the government on autopilot and I don't think that is a wise thing to do."

The Arizona Republican, who introduced a bill to ensure that those who have continued to work without a paycheck receive compensation, said the House-passed legislation could allow those who aren't working to be compensated for months.

"Let's say this thing went on for another three, four, five, six months. You would have people that didn't work at all being paid money from the federal government," he said.

About 420,000 federal employees deemed "essential" are working without pay during the shutdown, while about 380,000 have been furloughed.

Gosar issued a statement after the vote saying the bill removes an incentive to resolve the shutdown swiftly.

"This ill-conceived legislation takes away a useful tool in holding government accountable," he said. "Shutdowns have historically served to push both parties to compromise and resolution. This bill eliminates the impact and urgency a shutdown creates and rewards bureaucrats and swamp dwellers."

Massie made similar remarks in a statement saying the bill "guarantees retroactive pay for every possible future shutdown, which will only make it easier for politicians to cause future shutdowns."

"This is irresponsible and I want to prevent future shutdowns from happening," he said.

Updated at 7:09 p.m.