John Gill Commentary Mark 15:36

"And one ran, and filling a sponge full of vinegar, put it on a reed, and gave him to drink, saying, Let be; let us see whether Elijah cometh to take him down." — Mark 15:36 (ASV)

And one ran and filled a sponge full of vinegar
Christ at the same time saying, I thirst; see (John 19:28) ;

and put it on a reed ;
an hyssop stalk, (John 19:29) ;

and gave him to drink ;
and so fulfilled a prophecy in (Psalms 69:21) ;

saying ,
or "they said", as the Syriac version reads it; not he that fetched the sponge, but the others that were with him, and which agrees with (Matthew 27:27Matthew 27:49) ;

let alone ;
as forbidding him to go near him, and offer him any thing to drink:

let us see whether Elias will come and take him down ;
from the cross; (See Gill on Matthew 27:49).