"...idolatry can be active in my heart even as I’m outwardly worshipping God. That’s a sobering thought. Whenever I think I can’t worship God unless “X” is present, I’m making a profound statement. If “X” is anything other than Jesus Christ and the Holy Spirit, I’ve moved into idolatrous territory. Idolatry is always evil, but the idols we pursue aren’t necessarily evil things. They are evil for us because we value them over God."
Bob Kauflin, Idolatry on sunday mornings (read the full thing here: part 1, part 2)