the coexistence of the Father, Son, and Spirit within a divine unity." Catholic historian Joseph F. Kelly, speaking of legitimate theological development, writes: "The Bible may not use the word 'Trinity', but it refers to God the Father frequently; the Gospel of John emphasized the divinity of the Son; several New Testament books treat the Holy Spirit as divine. The ancient theologians did not violate biblical teaching but sought to develop its implications. ... [Arius'] potent arguments forced other Christians to refine their thinking about the Trinity." "At two ecumenical councils, Nicea I in 325 and Constantinople I in 381, the church at large defined the Trinity in the way now so familiar to us from the Nicene Creed. This exemplifies development of doctrine at its best. The Bible may not use the word 'Trinity', but trinitarian theology does not go against the Bible. On the contrary, Catholics believe that trinitarianism has carefully developed a biblical teaching for later generations." Questions about co-equal deity of Jesus American Catholic priest and Trinitarian, R.E. Brown (1928–1988), wrote a journal article that sorted relevant biblical verses into three classes. He described the following block as "texts that seem to imply that the title 'God' was not used for Jesus" and are "negative evidence which is often somewhat neglected in Catholic treatments of the subject": , , , , , , , , , , , , , , , and ; he lists these as "texts where, by reason of textual variants or syntax, the use of 'God' for Jesus is dubious": , Acts 20:28, , , , , , and ; and only finds the following three as "texts where clearly Jesus is called God": , John 1:1, and John 20:28. The Septuagint translate (Elohim) as θεος (Theos). At Deuteronomy 6:4 (the Shema Yisrael, quoted by Jesus at ), the plural form of the Hebrew word "God" (Elohim) is used, generally understood to denote majesty, excellence, and the superlative. It has been stated that in the original Greek in Mark 12:29, there are no "plural modifiers" in that Greek word there for "one" (heis), but that in Mark 12 it is simply a masculine singular "one". And that because of that, there is no valid reason to believe that the Hebrew word for "one" in Deuteronomy 6 (echad) was necessarily a "plural one", rather than just simply numerical "one". At Deuteronomy 6:4,