The early 'church fathers' did not want the persecution the Jewish believers were receiving at the hands of the Gk/Roman authorities who had pronounced Sunday the venerable day of the Sun, let the magistrates and people rest, and workshops be closed.
The "names" of YHWH (HaShem, G-d) in the TaNaKh are not "names" but are characteristics of HaShem. The TaNaKh is composed of The Torah ("Teaching", also known as the Five Books of Moses), Nevi'im ("Prophets") and Ketuvim ("Writings")—hence TaNaKh]. Praised be His glorious Name forever and ever.
Torah study is the study by Jewish people of the Torah, Hebrew Bible, Talmud, responsa, rabbinic literature and similar works, all of which are Judaism's religious texts. According to Rabbinic beliefs the study is ideally done for the purpose of the mitzvah ("commandment") of Torah study itself.