The king gave scrupulous attention to the education of his children. They were brought up in simplicity and sternness, but received a manifold training and a great amount of instruction. While they were studying at Upsala, hams and butter were sent them from the royal estates to make part of their breakfasts and suppers. In spite of these patriarchal endeavors, Eric and John grew up to be typical Renaissance princes, fond of extravagance and luxury. The king wrote once to Duke Magnus: “Our dear Lady Catherine sends thee five shirts which thou must bear in mind to take good care of; _item_, to keep thy head clean and not ride or run too much.” When his sons grew older, King Gustavus used to admonish them orally before the hearth or at the table, or by letters. His wise counsel recalls the terse and sharp advice of Havamal in the Edda: “Ye shall weigh all matters carefully, perform them quickly and stand by it, putting nothing off to the morrow; counsel not followed up in due time is like clouds without rain in times of dearth.” “To speak once and stand by it, is better than to talk one hundred times.” “Surround ye ever with able men of pure living; one shall believe of ye what one knows about them.” Duke Eric early caused him trouble by stubbornness, defiance and vanity. Duke John, the oldest child of Queen Margaret, long remained his favorite, but ended by causing him grief through disobedience and secret conspiracy with Eric. In his old age, King Gustavus suffered through failing health and melancholy. He complained because the fate of his country seemed uncertain on account of the unstability of his sons, and because his old friends, like John Turesson and Christine Gyllenstierna, passed away before him, leaving him alone in the world. When King Gustavus felt that the end was drawing near, he sent word to the four Estates or representative classes of the country, the nobles, clergymen, burghers and yeomen, to meet him at Stockholm around the Midsummer of 1560. He made known to the Estates his will, which his sons pledged themselves by oath to fulfil. Eric should inherit the crown, according to the will, but the three other sons were to receive duchies which they should govern with a good deal of authority. It became evident that the king had taken pains to provide liberally for his sons. But it appears as if he intended to make them all responsible in the maintenance of the work of their father, by distributing the power between them. When the Estates had collected in the hall of state the old monarch entered with his sons. After greeting those present he delivered his farewell address: