app.js

var contacts = require('./routes/contacts');
var passport = require('passport');

// passport configured and working
// ...

app.use('/contacts/', contacts);

contact.js

var passport = require('passport');
var express = require('express');
var router = express.Router();
var Account = require('../models/account');
var Contact = require('../models/contact');

router.use(passport.authenticate('local', { failure: '/auth/login' }));

router.get('/', function(req, res) {
  Contact.find( function(err, contacts, count) {
      res.render('list', {contacts: contacts});
  });
});

// router.get('/', passport.authenticate('local'), function(req, res) {
//   Contact.find( function(err, contacts, count) {
//       res.render('list', {contacts: contacts});
//   });
// });