The first church? 4th Century Church of the Ark found on West Bank
How about polygamy? Evangelical Outpost
Ancient prayers, at Real Meal. One example (Origen, 185-254):
Lord, inspire us to read your Scriptures and meditate upon them day and night. We beg you to give us real understanding of what we need, that we in turn may put its precepts into practice. Yet we know that understanding and good intentions are worthless, unless rooted in your graceful love. So we ask that the words of Scriptures may also be not just signs on a page, but channels of grace into our hearts. Amen.
On Advent, from Frederick Buechner's Whistling in the Dark (h/t, It Takes a Church):
The house lights go off and the footlights come on. Even the chattiest stop chattering as they wait in darkness for the curtain to rise. In the orchestra pit, the violin bows are poised. The conductor has raised his baton. In the silence of a midwinter dusk, there is far off in the deeps of it somewhere a sound so faint that for all you can tell it may be only the sound of the silence itself. You hold your breath to listen. You walk up the steps to the front door. The empty windows at either side of it tell you nothing, or almost nothing. For a second you catch a whiff of some fragrance that reminds you of a place you've never been and a time you have no words for. You are aware of the beating of your heart…The extraordinary thing that is about to happen is matched only by the extraordinary moment just before it happens. Advent is the name of that moment.