Passage
This thou knowest, that all they which are in Asia, be turned from me: of which sort are Phygellus and Hermogenes.
2 Timothy 1:15 (GNV)
Nearby Context
2 Timothy 1:13 Keepe the true paterne of the wholesome wordes, which thou hast heard of me in faith and loue which is in Christ Iesus.
2 Timothy 1:14 That worthie thing, which was committed to thee, keepe through the holy Ghost, which dwelleth in vs.
2 Timothy 1:15 This thou knowest, that all they which are in Asia, be turned from me: of which sort are Phygellus and Hermogenes.
2 Timothy 1:16 The Lord giue mercie vnto the house of Onesiphorus: for he oft refreshed me, and was not ashamed of my chaine,
2 Timothy 1:17 But when he was at Rome, he sought me out very diligently, and found me.
Study Lenses
The verse centers on "thou", "knowest", "asia", "turned", "sort", "phygellus", and "hermogenes". It is saying that the verse draws attention to "thou" and "knowest", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 14's "That worthie thing which was committed to..." into verse 16's "The Lord giue mercie vnto the house...", so "thou" and "knowest" belong inside that flow. In 2 Timothy context, the local focus is Christ, faith, and discipleship.
A plain takeaway is to answer the verse's own emphasis on "thou" and "knowest" with trust shaped by these words, not by a vague optimism outside the passage.