Aquinas" second way is very similar to his first and often no distinction is made. It is based on the ideas of cause and effect. Aquinas observed the universe and concluded that nothing could cause itself and that the series of cause/effects "is not possible to go on to infinity." Therefore Aquinas closed by saying there must be a "first cause" which in itself is uncaused. .
Aquinas" third was delves into the notion of things being either contingent or necessary. Something labeled contingent has the possibility to exist or not exist and therefore at one point in time nothing that was contingent did exist. In third way Aquinas refers to God as a necessary being, something which has to exist and is not dependent on anything else for its existence. Aquinas called on people to respond to this conclusion by admitting "the existence of some being having of itself its own necessity." He went a step further to say "this all men speak of as God." .
The Kalam version is the Islamic part of the cosmological argument originating from the Muslim scholars: al-Kindi and al-Ghazali. William Lane Craig developed the modern Kalam argument in 1979. This argument is different from Aquinas" as it specifically deals with the issue of time and the universe being finite whilst Aquinas was happy to accept the possibility that the universe was infinite whereas he rejected infinite regress within the universe. Craig rejected actual infinities on the basis that the present is only a result of chronological events (or days) in the past and that this kind of addition of days would not be possible in an infinite world therefore the universe is finite requiring a beginning. Ed Miller continued this argument about the passage of time relating time as a signal of the beginning of the universe. .
Craig personally took the argument further than simply leaving it that the universe had a beginning; in his book "the Kalam Cosmological Argument".