I know thy works: behold, I have set before thee an open door, and no man can shut it: for thou hast a little strength, and hast kept my word, and hast not denied my name.
I have set - `given;' my gracious gift to thee.
Open door - for spiritual usefulness. The opening of a door by Him to the Philadelphian church accords with His having "the key of David."
And. A B C, Origen, 'which no man can shut.'
For - `because.'
A little. This gives the idea that Christ sets before Philadelphia an open door, because she has some little strength: rather, He does so because she has 'but little strength:' consciously weak herself, she is the fitter object for God's power to rest on (Aquinas), that Christ may have all the glory (2 Corinthians 12:9-10).
And hast kept - and so, the littleness of thy strength leading thee to rest wholly on My great power, thou didst keep my word. Grotius explains "little strength," that she had a church small in numbers and external resources: 'of small account in the eyes of men' (Trench). Aorist, 'Thou didst not deny my name,' on some particular occasion, when thy faithfulness was put to the test.