A.T. Robertson Commentary 1 Corinthians 16:5

"But I will come unto you, when I shall have passed through Macedonia; for I pass through Macedonia;" — 1 Corinthians 16:5 (ASV)

When I shall have passed through Macedonia (οταν Μακεδονιαν διελθω). "Whenever I pass through (second aorist active subjunctive of διερχομα) Macedonia" (see construction in verse 3).

I do pass through (διερχομα). I plan to pass through, futuristic use of present indicative.