OK, accept, accredit, acknowledge, affirm, allege, amen, and candle, approve, ascertain, assert, assert under oath, asseverate, assure, attest, authenticate, authorize, autograph, aver, avouch, avow, back, back up, be sponsor for, bear out, bear witness, bolster, bond, book, buttress, certificate, charter, cinch, circumstantiate, classify, clear up, clinch, commission, confirm, corroborate, cosign, countersecure, countersign, decide, declare, depone, depose, determine, disclose, dismiss all doubt, document, empower, enable, endorse, enfranchise, ensure, entitle, establish, find out, fix, fortify, franchise, get at, give evidence, give official sanction, give permission, give power, give the go-ahead, give the imprimatur, give thumbs up, guarantee, guaranty, initial, insure, kiss the book, legalize, legitimize, license, make certain, make no doubt, make no mistake, make sure, make sure of, nail down, notarize, pass, pass on, pass upon, patent, permit, privilege, probate, profess, prove, ratify, reassure, reinforce, remove all doubt, rubber stamp, sanction, say amen to, seal, second, secure, see that, see to it, set at rest, settle, sign, sign and seal, sign for, sort out, sponsor, stand behind, stand up for, strengthen, subscribe to, substantiate, support, sustain, swear, swear and affirm, swear by bell, swear the truth, swear to, swear to God, swear to goodness, testify, undergird, undersign, underwrite, uphold, validate, verify, visa, vise, vouch, vouch for, vouchsafe, vow, warrant, witness
be evidence, evince, show, betoken, tell of, indicate, imply, involve, argue, bespeak, breathe, have weight, carry weight, tell, speak volumes, speak for itself, rest upon, depend upon, repose on, bear witness, give evidence, testify, depose, witness, vouch for, sign, seal, undersign, set one's hand and seal, sign and seal, deliver as one's act and deed, certify
, attest, acknowledge, make absolute, confirm, prove (demonstrate), indorse, countersign, corroborate, support, ratify, bear out, uphold, warrant, adduce, attest, cite, quote, refer to, appeal to, call, call to witness, bring forward, bring into court, allege, plead, produce witnesses, confront witnesses, place into evidence, mark into evidence, collect evidence, bring together evidence, rake up evidence, experiment, have a case, make out a case, establish, authenticate, substantiate, verify, make good, quote chapter and verse, bring home to, bring to book.
assert, make an assertion, have one's say, say, affirm, predicate, declare, state, protest, profess, put forth, put forward, advance, allege, propose, propound, enunciate, broach, set forth, hold out, maintain, contend, pronounce, pretend, depose, depone, aver, avow, avouch, asseverate, swear, make oath, take one's oath, make an affidavit, swear an affidavit, put in an affidavit, take one's Bible oath, kiss the book, vow, vitam impendere vero, swear till one is black in the face, swear till one is blue in the face, swear till all's blue, be sworn, call Heaven to witness, vouch, warrant, certify
, assure, swear by bell book and candle, swear by, insist upon, take one's stand upon, emphasize, lay stress on, assert roundly, assert positively, lay down, lay down the law, raise one's voice, dogmatize, have the last word, rap out, repeat, reassert, reaffirm, announce, acknowledge, attest, adjure.