Multilingualism is a key factor of the European integration. For a state and its citizens the language is a very sensitive issue. The accession of a new member state is usually connected with the use of a new official language of the European Union. The coexistence of people in a state is bound to the law and the law is bound to the language. The regulative function of the law requires exactness, but as shown in the Frege´s semantic triangle, the language reduces exactness of the norm through possibility of the interpretation. This problem is more visible if there is a translation of a norm from one language to another. The translation process necessarily creates mistakes and the final official language versions of the community norm are many times not identical in their meaning. The doctrine of the European Court of Justice states that interpretation of a provision of Community law involves a comparison of different language versions and the crucial role plays teleological approach to the interpretation of a community norm. But still there is a strong tension between legal certainty and the language expression of a norm. Can the knowledge of law be determined by a considerable language capability of the exploring entity?