Tes·ti·fy v. i. [imp. & p. p. Testified p. pr. & vb. n. Testifying ]
1. To make a solemn declaration, verbal or written, to establish some fact; to give testimony for the purpose of communicating to others a knowledge of something not known to them.
Jesus . . . needed not that any should testify of man, for he knew what was in man. --John ii. 25.
2. Law To make a solemn declaration under oath or affirmation, for the purpose of establishing, or making proof of, some fact to a court; to give testimony in a cause depending before a tribunal.
One witness shall not testify against any person to cause him to die. --Num. xxxv. 30.
3. To declare a charge; to protest; to give information; to bear witness; -- with against.
O Israel, . . . I will testify against thee. --Ps. l. 7.
I testified against them in the day wherein they sold victuals. --Neh. xiii. 15.