As long as Isaac Abrabanel enjoyed the king's favor, he was as a "shield and a wall for his race, and delivered the sufferers from their oppressors, healed differences, and kept fierce lions at bay," as described by his poetical son, Judah Leon. He who had a warm heart for all afflicted, and was father to the orphan and consoler to the sorrowing, felt yet deeper compassion for the unfortunate of his own people. When Alfonso conquered the port of Arzilla, in Africa, the victors brought with them, among many thousand captive Moors, 250 Jews, who were sold as slaves throughout the kingdom. That Jews and Jewesses should be doomed to the miseries of slavery was unendurable to Abrabanel's heart. At his summons a committee of twelve representatives of the Lisbon community was formed, and collected funds; then, with a colleague, he traveled over the whole country and redeemed the Jewish slaves, often at a high price. The ransomed Jews and Jewesses, adults and children, were clothed, lodged, and maintained until they had learned the language of the country, and were able to support themselves. When King Alfonso sent an embassy to Pope Sixtus IV to congratulate him upon his accession to the throne, and to send him tidings of his victory over the Moors in Africa, Doctor John Sezira was one of the ambassadors. One in heart and soul with Abrabanel, and friendly to the Jews, he promised to speak to the pope in their favor and behalf. Abrabanel begged his Italian friend, Yechiel of Pisa, to receive John Sezira with a friendly welcome, to place himself entirely at his disposal, and convey to him, and to the chief ambassador, Lopes de Almeida, how gratified the Italian Jews were to hear of King Alfonso's favor to the Jews in his country, so that the king and his courtiers might feel flattered. Thus Abrabanel did everything in his power for the good of his brethren in faith and race.