  An approach for relating the nucleon resonances extracted from $\pi N$
reaction data to lattice QCD calculations has been developed by using the
finite-volume Hamiltonian method. Within models of $\pi N$ reactions, bare
states are introduced to parametrize the intrinsic excitations of the nucleon.
We show that the resonance pole positions can be related to the probability
$P_{N^*}(E)$ of finding the bare state, $N^*$, in the $\pi N$ scattering states
in infinite volume. We further demonstrate that the probability $P_{N^*}^V(E)$
of finding the same bare states in the eigenfunctions of the underlying
Hamiltonian in finite volume approaches $P_{N^*}(E)$ as the volume increases.
Our findings suggest that the comparison of $P_{N^*}(E)$ and $P_{N^*}^V(E)$ can
be used to examine whether the nucleon resonances extracted from the $\pi N$
reaction data within the dynamical models are consistent with lattice QCD
calculation. We also discuss the measurement of $P_{N^*}^V(E)$ directly from
lattice QCD. The practical differences between our approach and the approach
using the L\"uscher formalism to relate LQCD calculations to the nucleon
resonance poles embedded in the data are also discussed.
