Ah; another link to another copy of the same words.  That's a kind thought, but I can't help but mention that it's redundant; it's always a good plan to read some of the postings on a thread -and look at the links already provided- before adding duplicate information.  I don't mean to sound unkind, but it really is a bit of a waste of time.

Further to Peg's comments:

It can often be difficult to assess the point at which two similar traditional songs become sufficiently distinct to be considered as quite separate; in this case, though, I see little doubt that As I Roved Out (as recorded by Planxty) and 16 Come Next Sunday (as recorded by the Bothy Band) are both variants belonging to the family of songs called by scholars Seventeen Come Sunday.  That family is large, and forms of it have been found in tradition throughout England, Scotland, Ireland (where it seems to be most popular in the North) and America.  While the tunes to which it is sung vary, as do details of the text, most recent versions are recognisably closely related.  Professor Child's #299, The Trooper and the Maid may well be an earlier form.  The version popularised by Planxty, for example, is close in both text and tune to others collected in England by Sharp and Hammond in the early 20th century; equally similar versions were recorded from such as Seamus Ennis (Ireland) and Walter Pardon (England) in the 1950s and '60s.  The tune used by the Bothy Band, though they give no source for it on their original recording, shows a distinct similarity to the tunes given in the DT for The Trooper and the Maid and Burns' Nine Inch Will Please a Lady; the latter, like the first Scottish version linked to below, specifies The Quaker's Wife as prescribed tune.  I'd also refer to  The Traditional Ballad Index:

Seventeen Come Sunday  [Laws O17]

Trooper and the Maid

They consider the Seventeen Come Sunday and Trooper and the Maid groups to be separate, though widely intermingled; by their generalised definition, however, As I Roved Out (as recorded by Planxty) would belong to the latter group, and the Bothy Band's 16 Come Next Sunday to the former.  If, however, we look at text and tune together, it seems clear that, if they do indeed belong to different groups, it is the Planxty song which is a Seventeen Come Sunday variant.  For myself, until I see more evidence, I'm sticking with Peter Kennedy, Frank Purslow etc. in considering the two strands as essentially the same song, and these two examples as related variants, the one carrying a tune variant from the Anglo-Irish tradition, the other from the Scottish.  Here are links to related entries in the DT:

Whaur are ye gaun, ma bonnie wee lass  -[a] Scottish version from Glasgow, [2] children's ring game.

A Waukrife Minnie  -the version collected (and likely modified) by Robert Burns.  With tune.

As I Roved Out  from Folksongs and Ballads Popular in Ireland, Ossian Publications.  This is the version recorded by Christy Moore with Planxty.  With tune.

The Trooper and the Maid  Scottish version, original source not specified.  With tune.

Malcolm