  Using a simple relativistic QFT model of scalar fields we demonstrate that
the analytic confinement (propagator is an entire function in the complex
$p^2$--plane) and the weak coupling constant lead to the Regge behaviour of the
two-particle bound states. In QCD we assume that the gluon vacuum is realized
by the self-dual homogeneous classical field which is the solution of the
Yang-Mills equations. This assumption leads to analytical confinement of quarks
and gluons. We extract the colorless $0^{++}$ two-gluon state from the QCD
generating functional in the one-gluon exchange approximation. The mass of this
bound state is defined by the Bethe-Salpeter equation. The glueball mass is
$1765~{\rm MeV}$ for $\alpha_s=0.33$ if the gluon condensate is
$<(\alpha_s/\pi) G G >=0.012~{\rm GeV}^4$.
