  We use a recently proposed formulation of stable holomorphic vector bundles
$V$ on elliptically fibered Calabi--Yau n-fold $Z_n$ in terms of toric geometry
to describe stability conditions on $V$. Using the toric map $f: W_{n+1} \to
(V,Z_n)$ that identifies dual pairs of F-theory/heterotic duality we show how
stability can be related to the existence of holomorphic sections of a certain
line bundle that is part of the toric construction.
