Sample data: -

IF object_id('tempdb..#testEnvironment') IS NOT NULL

BEGIN

DROP TABLE #testEnvironment;

END;

SELECT ID, Name

INTO #testEnvironment

FROM (VALUES(1, 'Fred'),(2, 'Joe'),(3, 'Bob'))a(ID, Name);

Query: -

DECLARE @Delimitedlist VARCHAR(8000) = '1,3,2';

SELECT STUFF((SELECT ','+a.Name

FROM #testEnvironment a

INNER JOIN (SELECT ItemNumber AS Ordering, Item

FROM dbo.DelimitedSplit8K(@Delimitedlist,',')

) b ON a.ID = b.Item

ORDER BY b.Ordering

FOR XML PATH(''), TYPE).value('.','NVARCHAR(MAX)'),1,1,'');

Result: -

Fred,Bob,Joe

dbo.DelimitedSplit8K function can be found here --> http://www.sqlservercentral.com/articles/Tally+Table/72993/%5B/url%5D.

Solution will only work if your original deliminated string is never more than 8000 characters.