The term 'rare' in this 17th Century receipt means 'exceptional', not 'under-cooked'.
Original Receipt in 'The Cooks Guide, or, Rare Receipts for Cookery' (1664) by Hannah Woolley (Wooley 1664)To Make Rare Bartlemas Beef
Take a fat Brisket piece of beef and bone it, put it into so much water as will cover it, shifting it three times a day for three dayes together, then put it into as much white wine and vinegar as will cover it, and when it hath lyen twenty-four hours take it out and drye it in a cloth, then take nutmeg, ginger, cinnamon, cloves and mace, of each a like quantity, beaten small and mingled with a good handful of salt, strew both sides of the Beef with this, and roul it up as you do Brawn, tye it as close as you can; then put it into an earthen pot, and cover it with some paste; set it in the Oven with household bread, and when it is cold, eat it with mustard and sugar.