Cleansing Fire has written a beautiful reflection on the sacredness of churches.
It's Just a Building
She begins with a quote from Psalm 84, which happens to be in today's Morning Prayer: How lovely are your tabernacles, O Lord of hosts! 3 My soul longs and faints for the courts of the Lord. My heart and my flesh have rejoiced in the living God. 4 For the sparrow has found herself a house, and the turtle a nest for herself where she may lay her young ones: Your altars, O Lord of hosts, my king and my God. 5 Blessed are they that dwell in your house, O Lord: they shall praise you for ever and ever.