Mark 15:6

Now at that feast ,.... The feast of the passover, which was at that instant; see John 18:39 . The Syriac, Arabic, Persic, and Ethiopic versions read, "at every feast"; as if the following custom was used at every feast in the year, at the feasts of pentecost and tabernacles, as well as at the passover; whereas it was only at the latter:

he released unto them one prisoner, whomsoever they desired ; of this custom See Gill on Matthew 27:15 .