Through the ages Jewish apostates have often been a thorn in the side of Jewish communities they left behind. Names such as Donin and Pfefferkorn (to mention a small sampling) evoke bad memories, not only because they were perceived as traitors and followers of falsehood but also because men such as these waged war on the Jews they left behind. Nicholas Donin and Pablo Christiani goaded secular authorities in forcing Jews to debate them. If the speech of the Jewish disputant wasn't restricted, one or even both hands were still tied behind their back since they could not be sure that debating freely wouldn't lead to severe consequences. Johannnes Pfefferkorn waged a war on the Talmud and managed to obtain edicts against the Talmud. (See further in Rodkinson's Talmud introduction.)
However, not all apostates were antisemitic or anti-Judaism. Benjamin D'Israeli maintained fond feelings for Jews and Judaism throughout his life (his father, who converted him as a child? Well, not so much. "[The Talmud] is a complete fyftem of barbarous learning of the Jews.")
Christian David Ginsburg was one of the most famous and accomplished Bible scholars of the 19th century. Born a Jew in Warsaw in 1831 (as you'd imagine, they said "Duvid" at his bris and not Christian David) and in receipt of a traditional yeshiva education, he eventually converted to Christianity while a teenager (under what influence and circumstances, I have no idea) and parlayed his early education into a career as a Bible scholar and missionary of note. He prepared a Hebrew translation of the New Testament intended, obviously, to aid in converting Jews. He wrote a still-valuable introduction to Tanakh called the "Introduction to the Massoretico-critical edition of the Hebrew Bible." Working with rare and valuable Hebrew manuscripts at the British Museum (now the British Library) he produced a monumental four volume work called "The Massorah, compiled from manuscripts alphabetically and lexically arranged," which you can download here). He produced high quality Bibles, wrote numerous essays on Jewish subjects and many entries for the excellent "Cyclopaedia of Biblical Literature," originally edited by John Kitto (1862-66). He was involved in debunking the Shapira forgery (posted about here, here, here and here).
In any case, let us get to the point of this post already! There is no question that valuable though some of his contributions were, he fairly well assimilated into British society (but for de eccent, I guess) and apart from trying to convert Jews (which they always love, dontcha know?) he as most definitely a Christian David, not a Duvid. But he obviously always maintained an abiding and respectful interest in his heritage and he also knew a thing or two and most importantly, he usually managed to avoid letting his personal religious bias color his interpretation of Judaism's sacred texts when explicating the Jewish point of view.
Furthermore, he seems to have had some romantic notions about Jewish scholars. Read the following excerpt from his entry on the book of Ecclesiastes in Kitto's Cyclopaedia. Note that the audience was to be Christian.
Since I would like this text to be google searchable, I will post some of it:
"[literary Jew[s like] Geiger...Luzzatto...Zunz...Krochmal...Jost...Steinschneider...Graetz...and a host of others affirm that this book is one of the latest productions in the O.T. canon. And be it remembered that these are men to whom Hebrew is almost vernacular, and that some of them write better Hebrew, and in purer style, than that of Coheleth."
One imagines a tiny swell of pride in his chest as he wrote this exaggeration for his learned audience.
(On the attitude of Jews toward him, see this post and also this one. On a translating blunder made by him because of religious bias, see here.)