No complex economy can exist without a credit system. Credit certainly preceded the emergence of formal coinage. Banking, in a rudimentary form, was present before mints were in existence. When we try to understand a financial instrument or institution, we must consider at least three aspects:
Through time all three may change in every combination. For example, today banks serve as places for the deposit and safe-keeping of valuables, but historically these functions were served by places of worship, temples and fortified palaces. Deposit dates from at least Babylonian times. In more recent times, in the 12th century the Jews of York used the York Minster and the goldsmiths of London used the Tower of London.
Examples of the earliest recorded credit instruments are provided by letter-orders, of the form: "Say to NN, may he giveƒ to (the bearer)".
One can debate whether or not we can regard these as checks. But when one reads the boiler plate on a current bank check the prime function is essentially the same.