The latter spelling is now more usual. The term was applied to a popular literary form in the ancient world where it was defined as ‘a concise reminiscence aptly attributed to some character’. Chreiai might be jokes or maxims or examples, and it was part of the education of students to compose them, or to expand a concise chreia into a whole paragraph.
Form Critics of the NT (e.g. Martin Dibelius) in the first part of the 20th cent. used the term for the category of short pointed sayings of general significance but originally spoken to a particular person or within a definite situation. No circumstantial details are included. An example is: ‘Let the children come to me; do not stop them; for it is to such as these that the kingdom of God belongs’ (Mark 10: 14). Other examples are Mark 2: 4 f. and Luke 11: 27 f.
A concise chreia could, however, be expanded, as in Mark's account of Jesus' Cleansing of the Temple (11: 11–15), while Luke (who had previously mentioned Jesus' first entries into the Temple at 1: 22 and 2: 41) condenses Mark's expanded chreia into a concise one (Luke 19: 45–6).