When Tomas leaves the church to go to the scene of the suicide there is a lot of snow on his car and on the ground. But, when he arrives at the scene, the car is clean and there is no sign of snow on the ground.
In the vestry (or office) to the side of the church, as Tomas realises that he believes life is more understandable without the presence of God, the light through the window behind him intensifies. Assuming the church building has an east-west orientation (as churches tend to do), the light is coming from a northerly direction. Yet, when he later re-enters the church proper (and collapses by the altar rail), the sun is clearly visible, low in the sky, through the window at the opposite (southern) side of the building.
Märta's near-sightedness is mentioned in the dialogue when she says that without her glasses, Tomas appears fuzzy to her. He even counts her nearsightedness as one of the things he hates about her. But the lenses she wears appear to be of clear glass.