Albert Barnes on Matthew 27:7

And they took counsel, etc. They consulted among themselves about the proper way to dispose of this money.

And bought with them. In Acts 1:18, it is said of Judas that he "purchased a field with the reward of iniquity." By the passage in the Acts is meant no more than that he furnished the means, or was the occasion of purchasing the field. It is not of necessity implied that Judas actually made the contract, and paid down the money to buy a field to bury strangers in--a thing which would be in itself very improbable; but that it was by his means that the field was purchased. It is very frequent in the Scriptures, as well as in other writings, to represent a man as doing that which he is only the cause or occasion of another's doing. See Acts 2:23, Jn 19:1, Mt 27:59,60.

The potter's field. Probably this was some, field well known by that name, which was used for the purpose of making earthen vessels. The price paid for a field so near Jerusalem may appear to be very small; but it is not improbable that it had been worked till the clay was exhausted, and was neither fit for that business nor for tillage, and was therefore considered as of little value.

To bury strangers in. Jews, who came up from other parts of the world to attend the great feasts at Jerusalem. The high priests, who regarded the Gentiles as abominable, would not be inclined to provide a burial-place for them.