Eisen took the drop of holy water. His hammer was blessed by pope Pope Sixtus IV in the 13th century when his ancestors started hunting witches, but he didn't know if it really had holy properties or not. He did not understand enough of the arcane to risk condemning some poor soul to purgatory for his incompetence so he decided to put a drop of the water on his hammer just in case. He had an hour from now to make it count but that's all he needed. Worse case scenario he could just cripple a zombie to make it nonthreatening to anyone until they destroyed the source.