Emily Dickinson Lexicon

SWEAR, v.t.

1. To utter or affirm with a solemn appeal to God for the truth of the declaration; as, to swear on oath. [This seems to have been the primitive use of swear; that is, to affirm.]
2. To put to an oath; to cause to take an oath; as, to swear witnesses in court; to swear a jury; the witness has been sworn; the judges are sworn into office.
3. To declare or charge upon oath; as, to swear treason against a man.
4. To obtest by an oath. Now by Apollo, king, thou swear'st thy gods in vain. – Shak. To swear the peace against one, to make oath that one is under the actual fear of death or bodily harm from the person; in which case the person must find sureties of the peace.