Vulnerability is a highly relevant topic for Bioethics, as well as for Theological Ethics and the other Sciences once one realizes how much worry about survival issues in our planet has been expressed worldwide. The core of these issues is Man, the one who plays the most important part in History, in the global cultural memory and in every-day life, and consequently the one who needs to be taken care of. In this dissertation, the question of vulnerability and that of the quality of life are brought close together so as to show how one relates to the other, with the contribution of the Ethic-theological reasoning, establishing a dialog with the Bioethics, including and highlighting the importance of difference, social and economical injustices, and of contextualization, without neglecting the passion for life. Seeing the connection between the vulnerabilities, the quality of life and the hope for better days is important to the sustainability of the human progress on Earth. The international declarations, the ethical codes and the Catholic Church documents together with various other manifestations show the urge for balanced, controlled development so that the present and the next generations can hope for a decent and sound life. This dialog with the Bioethics is mandatory in the sciences. In this aspect, the Theological Ethics comes into scene through studies and religious practice that claim that life quality and life itself have to go hand in hand. This search for more qualitative and intense relations is fundamental to the Theological Ethics, since what Jesus practiced himself reflected how clearly the Good News was announced to all living creatures, especially the most vulnerable and miserable.