I had no rest in my spirit, because I found not Titus my brother: but taking my leave of them, I went from thence into Macedonia.
No rest in my spirit - rather 'no rest for my spirit' (Genesis 8:9). As here his "spirit" had no rest, so in 2 Corinthians 7:5, his "flesh." His "spirit" - not from mere human impulse, but under the Holy Spirit-hence concluded that it was not necessary to avail himself of the "door" of usefulness at Troas any longer.
Taking my leave of them - the disciples at Troas.