Pasteur vs Abiogenesis

A common fallacy among creationists is that Pasteur disproved abiogenesis. Here are some examples:

One of Pasteur’s first major scientific contributions was disproving the supposed spontaneous generation of living things (such as bacteria) from non-living organic matter. (However in spite of this disproof, spontaneous generation is now considered to be the foundation of the evolutionary view of the origin of life if “millions of years” are added).

http://www.answersingenesis.org/articles/aid/v4/n1/creation-germ-theory

Louis Pasteur destroyed the belief that life could be created from inanimate substances.

http://www.darwinismrefuted.com/short_history_02.html

However, Louis Pasteur was in the very process of proving that spontaneous generation of cellular life was even more illusory than the flat earth.

http://www.answersingenesis.org/articles/cm/v23/n1/life

The Law of Biogenesis is real, and accepted as true by all scientists. Evolution cannot be true, because it is against this law. To have a law there must be a law-giver. Who gave us the Law of Biogenesis? That Law-Giver could only be God.

http://www.discoverymagazine.com/articles/d1992/d9204g.htm

The law of biogenesis plainly teaches that all life comes from preexisting life, and that of its kind. That is exactly what the Bible always has taught as occurring in nature.

http://www.evolutionisdead.com/quotes.php?QID=018

Prior to Pasteur, most people believed that complex organisms could appear spontaneously. For example, maggots appeared spontaneously in rotting meat, snakes from piles of hay. Of course, the reason for these beliefs was that they had failed to see the eggs being laid. Rats, mice, barnacle geese and crocodiles were all thought to appear by a process called "spontaneous generation"

What was it that Pasteur actually did, and what conclusions can we draw from his experiments?

In the midst of the great excitement and controversy created by Pasteur's research on fermentation, a debate was ongoing in the scientific world on the theory of "spontaneous generation". The idea that beetles, eels, maggots and now microbes could arise spontaneously' from putrefying matter was speculated on from Greek and Roman times. ... The experimental design that clinched the argument was the use of the swan-neck flask. In this experiment, fermentable juice was placed in a flask and after sterilization the neck was heated and drawn out as a thin tube taking a gentle downward then upward arc -- resembling the neck of a swan. The end of neck was then sealed. As long as it was sealed, the contents remained unchanged. If the the flask was opened by nipping off the end of the neck, air entered but dust was trapped on the wet walls of the neck. Under this condition, the fluid would remain forever sterile, showing that air alone could not trigger growth of microorganisms. If, however, the flask was tipped to allow the sterile liquid to touch the contaminated walls and this liquid was then returned to the broth, growth of microorganisms immediately began.
In the words of Pasteur "Never will the doctrine of spontaneous generation recover from the mortal blow of this simple experiment. No, there is now no circumstance known in which it can be affirmed that microscopic beings came into the world without germs, without parents similar to themselves."

http://louisville.edu/library/ekstrom/special/pasteur/cohn.html

The theory of spontaneous generation was finally laid to rest in 1859 by the young French chemist, Louis Pasteur. The French Academy of Sciences sponsored a contest for the best experiment either proving or disproving spontaneous generation. Pasteur's winning experiment was a variation of the methods of Needham and Spallanzani. He boiled meat broth in a flask, heated the neck of the flask in a flame until it became pliable, and bent it into the shape of an S. Air could enter the flask, but airborne microorganisms could not - they would settle by gravity in the neck. As Pasteur had expected, no microorganisms grew. When Pasteur tilted the flask so that the broth reached the lowest point in the neck, where any airborne particles would have settled, the broth rapidly became cloudy with life. Pasteur had both refuted the theory of spontaneous generation and convincingly demonstrated that microorganisms are everywhere - even in the air. 

http://www.accessexcellence.org/RC/AB/BC/Spontaneous_Generation.html

See also (the last one has illustrations of the apparatus):
http://biology.clc.uc.edu/courses/bio114/spontgen.htm
http://www.kent.k12.wa.us/staff/TimLynch/sci_class/chap01/pasteur.html

The creationist argument goes like this:

1. Pasteur proved that life will not form spontaneously from sterilised meat broth under an oxidising atmosphere in about a month (I am guessing the time span).
2. Therefore, life can only come from life (the Law of Biogenesis)
3. As this is a law, it must be universal
4. Therefore life cannot form from primordial soup under a reducing or neutral atmosphere over the course of a million years.

The argument is founded on changing what the of Law of Biogenesis actually says along the way, and so is fundamentally flawed.

As an aside, Darwin's theory actually depends on the law of biogenesis. Common descent says that every living organism has an ancestry that can be traced back to a single common ancestor; this would not be true if crocodiles, mice and maggots were generated spontaneously.