From: Rabbi Moshe Sofer
To: Rabbi Meir
Rabbi Meir asks whether candles from a church may be used in a synagogue — both those merely designated but never lit, and those actually lit then extinguished, if melted and reformed. The Chasam Sofer rules that unlit candles are clearly permitted since mere designation without action creates no prohibition, while for melted-and-reformed candles he finds support for leniency but concludes that one who is lenient does not lose, and one who is strict will be blessed.
Source: Shu"t Chasam Sofer OC §42