But when ye shall see the abomination of desolation,.... The Roman army encompassing Jerusalem, which was an abomination to the Jews, and an "impure sign" of their destruction, as the Syriac and Persic versions render it; and a desolating one to their nation, city, and temple:spoken of by Daniel the prophet, in Da 9:27.
This clause is omitted in the Vulgate Latin, and was not found by Beza, in two of his copies, and is thought to be transcribed from Matthew:standing where it ought not; round about the city, in the midst of it, and even in the temple: in one of Beza's exemplars it is added, "in the holy place", as in Matthew; and so it is read in the Ethiopic version:let him that readeth understand; either the passage in Daniel, or the citation of it by the evangelist, when he shall see this come to pass: this seems to be rather the words of the evangelist, than of Christ; since this was not written (and so not to be read), but spoken by Christ; and since his usual phrase was, "he that hath ears, let him hear": though indeed the same exhortation is in Matthew, and may be understood of Christ, as it may refer to the written prophecy in Daniel, and indeed to the Gospel, which might be read before this event came to pass: See Gill on "Mt 24:15".