  The relation between the chiral quark condensate in QCD sum rules and chiral
perturbation theory is clarified with the help of a low-energy theorem for the
scalar and pseudoscalar correlation functions. It is found that the quark
condensate should be identified with the non-normal-ordered vacuum expectation
value of quark-antiquark fields. Utilising results on flavour SU(3) breaking of
the quark condensate from QCD sum rules, the unphysical low-energy constant
H_2^r in the chiral Lagrangian, as well as next-to-leading order corrections to
the Gell-Mann-Oakes-Renner relation are estimated.
