What's your opinion?
The opposite of abjure is objure. Per the OED:
trans. To bind by or charge under oath; to urge.
- 1609 R. Cawdrey Table Alph., ― Obiure, binde by oath.
- 1993 Irish Times (Nexis) 9 Feb. 17 — We are objured, in our so-called freedom of monetary exchange, to be patriotic.
intr. To utter an oath, to curse. Obs.
- 1830 Fraser’s Mag. II. 178 ― As the people only laughed at him, he cried the··more vehemently; nay, at last, began objuring, foaming, imprecating.
It is not particularly common.
I am not very familiar with the term "abjure". I may have seen it before, but I do not recall its specific meaning, nor the context in which I saw it.
Here is how I quickly processed this question, and came up with the same answer as Billy ONeal -- despite not being familiar with the word. Note that the actual meanings of the words are as Billy ONeal looked them up; the guesses below are just approximations. Approximations are usually good enough to do well on a test like the SAT or GRE:
Here is an optional confirmation: