This paper will examine the similarities and differences between Thomas Aquinas’ concept of the common good with a similar concept in Islamic law, namely: public welfare. The concept of public welfare was always been part of Islamic jurisprudential thought however it was developed and thoroughly researched by al-Shatibi. The fact that Thomas Aquinas was influenced by Maimonides ideas and also that Maimonides might have influenced al-Shatibi, could explain the resemblance between Thomas Aquinas’ “common good” and al-Shatibi’s “public welfare”. The ideological and theoretical connection thus has many implications because it sheds light on historically shared democratic values in the Western and the Muslim world.