Stored Procedure To Retrieve UserId From Aspnet_Users

Im a bit confused on my programming skills.  I know how to add a user and password using the Membership.CreateUser class. 
   ' Define database connection
Dim conn As New SqlConnection("Server=localhostSqlExpress;" & _
"Database=lnp;Integrated Security=True")
' Create command
Dim comm As New SqlCommand( _
"SELECT oldLogId, oldPassword FROM userDetails WHERE (oldLogId = N'chuck') OR (oldLogId = N'top_dawg')", conn)
' Open connection
conn.Open()
' Execute the command
Dim reader As SqlDataReader = comm.ExecuteReader()
' Do something with the data
While reader.Read()
Dim partPassword = reader.Item("oldPassword")
' Adds underscore character and first 3 letters of password for distinct USER ID
Dim newUserID = reader.Item("oldLogId") & "_" & partPassword.SubString(0, 3)
' Create User if Valid
Try
Membership.CreateUser(newUserID, partPassword)
Catch ex As MembershipCreateUserException
' Code that is executed when an exception is generated
' The exception's details are accessible through the ex object
usersLabel.Text &= "<p><strong>Exception: " & newUserID & "</strong><br />" & ex.ToString() & "<br /><strong>Message: </strong><br />" & ex.Message & "</p>"
End Try
End While
usersLabel.Text &= "<p><strong>END OF RECORDS</strong></p>"
' Close the reader and the connection
reader.Close()
conn.Close()
 But now I want to do something in a Stored Procedure
  USE [lnp]
GO
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE PROCEDURE [dbo].[sp_createPortingDetailsWithUsers]
-- Add the parameters for the stored procedure here
@passUserId NVarChar(50),
@passPassword NVarChar(50)
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;

Membership.CreateUser(@passUserId, @passPassword)

Select SCOPE_IDENTITY()
END
But when I try to execute this in SQL SERVER MANAGEMENT STUDIO EXPRESS, I get an error near the line MEMBERSHIP.CREATEUSER(@passUserId,@passPassword)
Msg 102, Level 15, State 1, Procedure sp_createPortingDetailsWithUsers, Line 11
Incorrect syntax near 'Membership'.
 
What I want to do is create a user with a UserID and Password that I am passing from a table and then retrieve the USERID (unique identifier)  when I create the new user.
Can anyone suggest or show a tutorial on what I am doing wrong?
 I appreciate any assistance in advance,
Chuck