Scripture can be quoted in either italics or quotation marks, depending on the style guide being followed. It is important to be consistent within a document or publication.
Italics
Quotation Marks
Italics are equivalent to underlining.
Italics.
Essays require quotation marks.
No, Italics.
Movie titles require either italics or underlining.
No. Use italics or underline (I believe italics is the most current format).
Quotation marks are used to inform you of a quotation.
It should be italicized.
Quotation marks typically go before or after commas, depending on whether the comma is part of the quoted material. If the comma is part of the quoted material, it goes inside the quotation marks. If the comma is not part of the quoted material, it goes outside the quotation marks.
Yes, either quotation marks or italics are good.