No, unless the paint layer is very thin, it cannot be done earlier. An oil painting can be varnished after about a year for normal layer thickness, a few months earlier for very thin layers, and several years for thicker layers. CAUTION: If a varnish is applied too early, there is a risk that the solvent of the varnish will dissolve the oil in the paint that has not yet fully dried and bring it to the surface. If this happens, the painting may remain sticky for many months or even years, and dust adhesion is difficult to prevent.