From American Catholic.org
The esteem in which the Church holds Lawrence is seen in the fact that today’s celebration ranks as a feast. We know very little about his life. He is one of those whose martyrdom made a deep and lasting impression on the early Church. Celebration of his feast day spread rapidly.
He was a Roman deacon under Pope St. Sixtus II. Four days after this pope was put to death, Lawrence and four clerics suffered martyrdom, probably during the persecution of the Emperor Valerian.
Legendary details of his death were known to Damasus, Prudentius, Ambrose and Augustine. The church built over his tomb became one of the seven principal churches in Rome and a favorite place for Roman pilgrimages.
A well-known legend has persisted from earliest times. As deacon in Rome, Lawrence was charged with the responsibility for the material goods of the Church, and the distribution of alms to the poor. When Lawrence knew he would be arrested like the pope, he sought out the poor, widows and orphans of Rome and gave them all the money he had on hand, selling even the sacred vessels to increase the sum. When the prefect of Rome heard of this, he imagined that the Christians must have considerable treasure. He sent for Lawrence and said, “You Christians say we are cruel to you, but that is not what I have in mind. I am told that your priests offer in gold, that the sacred blood is received in silver cups, that you have golden candlesticks at your evening services. Now, your doctrine says you must render to Caesar what is his. Bring these treasures—the emperor needs them to maintain his forces. God does not cause money to be counted: He brought none of it into the world with him—only words. Give me the money, therefore, and be rich in words.”
Lawrence replied that the Church was indeed rich. “I will show you a valuable part. But give me time to set everything in order and make an inventory.” After three days he gathered a great number of blind, lame, maimed, leprous, orphaned and widowed persons and put them in rows. When the prefect arrived, Lawrence simply said, “These are the treasure of the Church.”
The prefect was so angry he told Lawrence that he would indeed have his wish to die—but it would be by inches. He had a great gridiron prepared, with coals beneath it, and had Lawrence’s body placed on it. After the martyr had suffered the pain for a long time, the legend concludes, he made his famous cheerful remark, “It is well done. Turn me over!”
The gridiron that is believed to be his deathbed is in San Lorenzo in Lucina, Italy. That's one of the things I love about being Catholic - we venerate the implements of torture that broke the bodies of the saints. These were sanctified by their blood, made holy by their witness of their love of Christ. Despite the cruelty and evil done through the use of such things - like St Lawrence's gridiron - the opposite of the tormentor's intentions resulted, through the grace of God: an increase in faith and hope in eternal life.