An Etymological Dictionary of the German Language/Annotated/bereit
bereit, adjective, ‘ready, prepared,’ from Middle High German bereit, bereite, Old High German bireiti, ‘ready and willing, obliging; armed, ready’; compare Anglo-Saxon gerœ̂de, rœ̂de, English ready; Gothic garaids, ‘appointed,’ does not correspond exactly. The word may belong to the root discussed under reiten (compare Old High German reita, ‘carriage’), with the original sense of ‘to equip with armour’; like fertig, it would thus mean properly ‘ready for a journey’; compare Old Irish ríadaim, ‘I am going on a journey,’ ríad, ‘practicable (of a route), passable.’ On account of the similarity in meaning compare fertig.