A.T. Robertson Commentary Revelation 11:3

"And I will give unto my two witnesses, and they shall prophesy a thousand two hundred and threescore days, clothed in sackcloth." — Revelation 11:3 (ASV)

I will give (δωσω). Future active of διδωμ. The speaker may be God (Beckwith) or Christ (Swete) as in 2:13; 21:6 or his angel representative (22:7,12ff.). The idiom that follows is Hebraic instead of either the infinitive after διδωμ as in 2:7; 3:21; 6:4; 7:2; 13:7,15; 16:8 or ινα with the subjunctive (9:5; 19:8) we have κα προφητευσουσιν (and they shall prophesy).

Unto my two witnesses (τοις δυσιν μαρτυσιν μου). Dative case after δωσω. The article seems to point to two well-known characters, like Elijah, Elisha, but there is no possible way to determine who they are. All sorts of identifications have been attempted.

Clothed (περιβλημενους). Perfect passive participle of περιβαλλω as often before (7:9,13; 10:1, etc.). But Aleph A P Q here read the accusative plural in -ους, while C has the nominative in -ο. Charles suggests a mere slip for the nominative, but Hort suggests a primitive error in early MSS. for the dative περιβεβλεμενοις agreeing with μαρτυσιν.

In sackcloth (σακκους). Accusative retained with this passive verb as in 7:9,13. See 6:12 for σακκος and also Mt 3:4. The dress suited the message (Matthew 11:21).