  The low energy dynamics of QCD is investigated with special attention paid to
the matching between QCD and chiral perturbation theory(ChPT), and also to some
useful algebraic chiral operator relations which survive even when we include
chiral loop corrections. It then allows us to evaluate the hadronic matrix
elements below the energy scale $\Lambda_{\chi} \simeq 1$ GeV. Based on the new
analyzes, we present a consistent prediction for both direct CP-violating
parameter $\epsilon'/\epsilon$ and $\Delta I =1/2$ rule in the kaon decays. In
the leading $1/N_c$ approximation, the isospin amplitudes $A_0$ and $A_2$ are
found to agree well with the data, and the direct CP-violating parameter
$\epsilon'/\epsilon$ is predicted to be large, which also confirms our early
conclusion. Its numerical value is $\epsilon'/\epsilon =
23.6^{+12.4}_{-7.8}\times 10^{-4}(Im\lambda_t/1.2\times 10^{-4})$ which is no
longer sensitive to the strange quark mass due to the matching conditions.
Taking into account a simultaneous consistent analysis on the isospin
amplitudes $A_0$ and $A_2$, the ratio $\epsilon'/\epsilon$ is in favor of the
values $\epsilon'/\epsilon = (20\pm 9)\times 10^{-4}$.
