The Gaelic Bill will not be enough to save the language, according to a Holyrood committee.
The language is in a fragile state, MSPs warn.
In a report, the parliament's education committee called for "real commitment" from the Scottish Executive to Gaelic teaching.
But the committee backed the general principles of the bill, which gives the Gaelic tongue official status.
It also sets up a Gaelic development board although its members will not have to understand the language.
The aim of the body - Bord na Gaidhlig - is to oversee the development of Gaelic, to "secure its status as an official language of Scotland" and to give guidance on Gaelic education.
Some critics have argued it is a weakness that the bill does not require members of Bord na Gaidhlig to be able to understand Gaelic.
But the MSPs' report said: "The committee accepts it would be desirable for members of Bord na Gaidhlig to have knowledge of Gaelic.
"But it does not believe that this should be prescribed in statute as there may be benefit in ministers having the flexibility to appoint members with, for example, experience of the development of another minority language."
The report criticised the fact that the bill will not cover public bodies controlled by Westminster, such as pensions offices or the Food Standards Agency.
Committee members stressed that the number of people able to speak, read or write Gaelic had fallen to 65,674 by 2001 - a drop of 20% in 20 years.
Demand for 'commitment'
Its convener, Liberal Democrat Robert Robert Brown, said MSPs were struck by the "fragile" condition of the Gaelic language.
"We are in no doubt that vigorous action has to be taken to secure the future and vibrancy of the Gaelic language, and that the bill provides the framework for this."
However, he warned: "This bill will contribute to securing the future of Gaelic but it will not be enough on its own.
"It has to be backed up by real commitment by the Scottish Executive to the language and the Gaelic community and, in particular, to Gaelic education."