If I understood well your intent, you can create a spatial view in SQL Server using this SQL:
CREATE VIEW my_spatial_view
FROM point_table pt
JOIN polygon_table plg
ON pt.Shape.STWithin(plg.Shape) = 1
Note: this assumes the geometry column is named Shape, as is the default is ESRI's data models.
You can then add this spatial view to your map in ArcMap, even if you don't register it in the geodatabase.
If the one thing you want to do is to filter out objects from one table based on a spatial relation, and assuming that the polygon table is on the same database then the point table, you can also use the Definition Query property of the point layer in ArcMap, setting a filtering condition like:
Shape.STWithin( (SELECT geometry::UnionAggregate(plg.Shape) FROM CML_FREG_PL plg) ) = 1
NOTE: This can potentially be less interesting in terms of performance, but lets you use the point layer as an editable layer (as long as it was originally register with the geodatabase).
NOTE 2: If your polygon layer only as one record, i.e., one polygon, you don't need to do the UnionAggregate, therefore it will be more efficient in terms of performance