Merkel sat impassively during the debate on the bailout, as Greens co-leader Anton Hofreiter criticised her government for taking a hard line during talks leading up to the accord on the new bailout.
"A German government leadership that acts like that damages the cohesion in Europe and thereby damages Germany by damaging our standing in Europe," Hofreiter said to applause.
In the Netherlands, Prime Minister Mark Rutte will face a no confidence motion on Wednesday, brought by his chief opposition rival over a broken campaign pledge not to provide additional emergency funding to Greece.
On Tuesday, the parliaments of Austria, Estonia and Spain voted to approve the bailout.
In Berlin, Schaeuble said Athens had clearly shifted ground in the last few weeks and was ready to reform.
He also reiterated the German view that it is imperative for the International Monetary Fund to stay on board. The IMF, however, says it won't unless Greece gets debt relief, while Germany is against cutting Greek debt.
"I am fairly confident that we (international creditors including the IMF) will reach a joint assessment of (Greece's) debt sustainability in October," said Schaeuble, reiterating that a debt haircut is not possible.
Last month, a record 65 lawmakers from the conservative camp broke ranks and refused to back the start of bailout talks. ($1 = 0.9059 euros)