testify to

testify to (something)

To give sworn testimony that something is true. The doctor was asked to testify to the extent of the plaintiff's injuries in the criminal negligence lawsuit against the construction company. I was happy to testify for Daniel's whereabouts on the evening in question, as I had been with him the whole night.
See also: testify, to
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

testify to something

to swear to something. I will testify to your whereabouts if you wish. I think I know what happened, but I would not testify to it.
See also: testify, to
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.

testify to

1. To make a statement based on personal knowledge in support of some asserted fact; bear witness to something: Many astronauts have testified to the thrill of weightlessness. The witness testified to the accuracy of the defendant's story.
2. To serve as evidence: The wreckage testifies to the strength of the storm.
See also: testify, to
The American Heritage® Dictionary of Phrasal Verbs. Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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References in periodicals archive ?
Estalella, who was on the San Francisco Giants with Bonds in 2000 and 2001, is expected to testify to firsthand knowledge that Bonds used steroids, the Web site said, citing an unidentified source with knowledge of the evidence.
Anderson served more than a year in prison for refusing to testify to the grand jury.
Von Ancken is self-effacing about the scope of his knowledge, but some of his recent projects testify to how respected the Grubb & Ellis appraisal department is in New York City.
That is, until I reached the conclusion: 'For this I was born, and for this I came into the world, to testify to the truth.' So much of PWRDF's role is of witness, to testify to the truth on behalf of the Anglican Church of Canada In testifying to the truth, PWRDF engages with the parishes and dioceses of the Anglican Church of Canada to ensure their involvement in the struggle for a more just and equitable world.
If you reach a point where you are uncomfortable or cannot testify to something the attorney wishes you to, say so--vigorously if necessary.
In addition to who testifies and what they testify to, Hume (1748/1977, p.
* Technical witnesses testify to the specific and formula-driven benefits of insurance; paid $175 an hour
Weeding out bad experts, sometimes called "hired guns" for their willingness to testify to anything for a fee, is not so easy.
As a result, Crouch related, the jury "found him not guilty due to lack of sufficient identifying witnesses who had been in closed meetings with him, that is, witnesses who could testify to that effect."
81: Testimony of Thomas Heavener, for instance, a witness appeared reluctant to testify to his saloongoing because his father was a juror.
This is an important study whose conclusions testify to the increasing sexual repression associated with Reformation and Counter-Reformation culture.
Umali said De Castro did not approach him personally, but allegedly relayed his intention to testify to his panel secretariat.