Merkel's comments, at an event marking the 30th anniversary of Kohl's rise to power, came hours after Germany's president ratified the eurozone's permanent €500 billion ($645 billion) rescue fund. That clears the way for it to start work next month.
Kohl was a driving force behind the euro and remains an iconic figure in Merkel's conservative party. Bailing out eurozone strugglers hasn't been popular in Germany and has caused particular unease in parts of Merkel's centre-right governing coalition.
Kohl's name is "inextricably linked" with Europe's currency union, Merkel said, adding that he recognized that "a common currency would make European integration irreversible."
Merkel added that "the euro is far more than a currency." But she also pointed to promises made when the euro was introduced to justify her hard-nosed approach to the crisis — helping struggling countries while insisting on deficit-cutting and economic reform efforts in exchange.
"The promise of stability also was linked with the introduction of the euro — we feel committed to this promise in the German government," Merkel said.
"We will continue to do everything necessary to develop the economic and currency union so that it is stabilized permanently — so we are fighting the causes of the current government debt crisis not with a single strike but with a sequence of measures."
Ratification in Germany, Europe's biggest economy, of the permanent eurozone rescue fund was delayed for months by court challenges, but the country's highest court cleared the way for it to go ahead earlier this month.
At Thursday's event, Merkel presented Kohl — the leader of West Germany and then reunited Germany from 1982 to 1998 — with a new postage stamp bearing his image.
Kohl, now 82, said he wants to continue helping work to further the "great aim" of European unity.