Devote the first-fruits of your day to the Lord

Venerable John Climacus ~ The Ladder of Divine Ascent
Step 26 ~ On Discernment

¶103. There is a demon who comes to us when we are lying in bed and shoots at us evil and unclean thoughts, so that when we do not stand for prayer and thus are not armed against them, we may fall asleep with these foul thoughts and then have foul dreams too.
¶104. There is an evil spirit, called the forerunner, who assails us as soon as we awake from sleep and defiles our first thought. Devote the first-fruits of your day to the Lord, because the whole day will belong to whoever gets the first start. It is worth hearing what an expert told me: 'From my morning,' he said, 'I know the course of the whole day.'

When we are lying in bed, let us be especially sober and vigilant

Venerable John Climacus ~ The Ladder of Divine Ascent
Step 15 ~ On Chastity

¶53. When we are lying in bed, let us be especially sober and vigilant, because then our mind struggles with the demons without our body, and if it is sensual, it readily becomes a traitor.
¶54. Always let the remembrance of death and the Prayer of Jesus, being of single phrase, go to sleep with you and get up with you; for you will find nothing to equal these aids during sleep.