John Gill Commentary Acts 25:26

"Of whom I have no certain thing to write unto my lord. Wherefore I have brought him forth before you, and specially before thee, king Agrippa, that, after examination had, I may have somewhat to write." — Acts 25:26 (ASV)

Of whom I have no certain thing
No certain crime, charge, or accusation; nothing of any moment or consequence, no particular thing, nothing but a heap of confused notions, of I know not who or what:

to write unto my lord ;
meaning the Roman emperor, under whom he served as governor of Judea:

wherefore I have brought him before you ;
the whole company then present:

and especially before thee, O King Agrippa ;
as being not only a man of eminence, dignity, and authority, but of knowledge in such matters, which the Jews accused Paul of; see (Acts 26:2Acts 26:3) .

That after examination had ;
of Paul, and his case;

I might have somewhat to write ;
concerning him, and the charges exhibited against him to the emperor.