archbishop of Venice. Born of a noble Venetian family, Laurence lived devoutly at home for several years before joining the Augustinian monastery of San Giorgio on the island of Alga. This became a congregation of canons regular in 1404. Laurence was ordained priest in 1406, became prior in 1407 and again 1409–21, and then general of the congregation 1424–31. During these years he wrote notable ascetical and mystical works, based on his perception of Eternal Wisdom. Early works treat the contemplative, later ones the apostolic life. The most important is De casto connubio Verbi et animae (1425).
In 1433 he was appointed bishop of Castello, which included part of Venice, by Eugenius IV. In 1451 Nicholas V reorganized the whole area by suppressing Castello, reconstituting Grado at Venice, and making Laurence its first bishop. As he was first in line of the new organization, he is often but incorrectly called Patriarch of Venice.
As bishop, Laurence was famous for personal austerity and generosity to the poor. He generally preferred to give food and clothes rather than money, as he had learnt by experience how easily cash handouts could be abused. So he gave money in small quantities only, specially to those too shy or too proud to ask for help. He generally preferred to delegate finances to his steward and to reserve his time and strength for the spiritual aspects of his office. This included peacemaking and other pastoral work, of which he was reckoned to be a model by contemporaries.
In his last illness very many clergy and layfolk came to see him, among them the beggars and the destitute. He died on a bed of straw on 8 January. Canonized in 1690, his feast is on the day of his consecration as bishop: 5 September. Paintings of him by Bellini and Segala survive at Venice.
Life by his nephew in AA.SS. Ian. I (1643), 551–63; other Lives by D. Rosa (1914), P. La Fontaine (1960), and S. Giuliani (1962); see also San Lorenzo Giustiniani nel V centenario della morte, 1456–1956 (1959); N.C.E., viii. 567–8; Bibl. SS., viii. 150–9.