Lord

प्रभुः (‘master, one with power/authority’) is preferred as the default title precisely because ईश्वरः carries a specific philosophical liability: in Advaita Vedānta, Īśvara is Brahman as viewed through māyā — a real but only provisionally real (vyāvahārika) qualified (saguṇa) manifestation, ultimately superseded by the attributeless (nirguṇa) Brahman beyond even Īśvara. Using ईश्वरः as Christ’s title risks an Advaita-trained reader hearing ‘Lord’ as naming something less than ultimate reality. प्रभुः avoids this specific subordination trap, though it must still be paired with explicit exclusive-Lordship language, since प्रभुः alone does not rule out being one master among several.