John Gill Commentary Acts 9:16

"for I will show him how many things he must suffer for my name`s sake." — Acts 9:16 (ASV)

For I will show him
In vision, and by prophecy, either now, or hereafter; or by facts, as they come upon him:

how great things he must suffer for my name's sake ;
such as weariness, pain, and watchings, hunger, thirst, fastings, cold, and nakedness, perils on various accounts, and from different quarters, stripes, scourges, imprisonment, shipwreck, stoning, and death, of which he himself gives a detail, (2 Corinthians 11:23–28) so that Ananias had no reason to be afraid to go to him, and converse with him, and do unto him as he was directed.