The differences that we face in the world today, make us think about the most diversified cultures and make us have an opinion about each of them. Specially when the topic is the world peace which is so discussed and where in the name of the differences the same peace is threatened, a different point of view when it comes to accepting those differences, whether it be politics, economics or religious, that point of view is made necessary. Dealing with those issues, this work intends to offer some contribution, with the intention of thinking and understanding those differences, in the light of God´s Word reveled. Considering the problems faced by the foreigner, found in the oracle of Is 56,1-8, in a time where there was a strong tendency of racial exclusion, the prophet show us a new way to understand the reality, inviting the people to accept the different because that would be the will of God. He shows that blood bounds are not so important; it´s more important to be faithful to God, those are the true ones, the members of the chosen people. In order to accomplish this goal, this work is formed of three steps. First of all, we´ll present the status quaestionis of Third Isaiah. Second of all, we´ll made the delimitation of the text of Is 56,1-8 analysing its form, redaction and theological field. Finally, we´ll present the historical situation of the near postexile and how to understand the text - the problem of the foreigner - in this historical context.