Emergency legislation allowing Northern Ireland's historic power-sharing deal to go ahead has been rushed through Parliament with all-party backing.
The legislation delays devolution by six weeks
NI Secretary Peter Hain hailed the "triumph of peace over conflict" as the deadline for devolution was effectively extended by six weeks.
It follows Monday's ground-breaking deal between the DUP and Sinn Fein to share power in a new Assembly on 8 May.
The NI St Andrews Agreement Act 2007 cleared all its stages without a vote.
It has received Royal Assent.
Mr Hain praised Mr Paisley's "courage and leadership" in engaging with Mr Adams at Stormont.
Mr Paisley told the Commons on Tuesday that it was a "good day" for the House, for the United Kingdom and for the "people of Ireland, north and south".
He said there was a "star of hope" that could lead to a bright future.
But he added: "It is only a star of hope and we must remember that.
"We are not nearly across the river and we have some very hard things to do, and some great sacrifices to be made, in order that this star will not be like many other stars."
Mr Paisley said it was a "work-in" rather than "a love-in we are engaged in".
He said they had raised with Sinn Fein the issue of the killing of Belfast man Robert McCartney, and said: "We did get the promise that something would be done."
Speaking in the House of Commons earlier, the DUP MP William McCrea said there was no place for Sinn Fein in government.
"As far as I am concerned Sinn Fein in the government is abnoxious to me. It makes me sick to the bottom of my stomach."
"Because my thoughts are with the innocent victims, both Protestant and Roman Catholic throughout this community, that have been slaughtered by the IRA and so-called loyalist terrorist organisations."
SDLP leader Mark Durkan said the developments of recent days had "vindicated" those who had always supported power-sharing, but voiced regret at past opposition to it by other parties.
"When people see parties who rejected those concepts then settling for and embracing those concepts they do have to wonder did we have to go through the suffering, the hurt, the political stalemate, the stagnation, the divisions that we went through - and the answer is that we didn't," he said.
"I know in recent times in this process, maybe because of our tolerance, our patience, our generosity, my party has lost seats.
"But I can live much more comfortably with lost seats than with what other parties have to live with - which is lost years, lost opportunities and lost lives."
Ulster Unionist MP Sylvia Hermon warned: "One of the greatest casualties yesterday was trust in the entire Northern Ireland ministerial team who gave undertakings and commitments in this House that there would be no emergency legislation to break through the 26 March deadline."
It is Sinn Fein policy not to take part in debates at Westminster.
The government hopes the bill will be law by midnight on Tuesday. Opposition parties have already pledged their support.