When Mrs. Fairfax had bidden me a kind good-night, and I had fastened my door, gazed leisurely round, and in some measure effaced the eerie impression made by that wide hall, that dark and spacious staircase, and that long, cold gallery, by the livelier aspect of my little room, I remembered that after a day of bodily fatigue and mental anxiety, I was now at last in safe haven. The impulse of gratitude swelled my heart, and I knelt down at the bedside and offered up thanks where thanks were due; not forgetting, ere I rose, to implore aid on my further path, and the power of meriting the kindness which seemed so frankly offered before it was earned. My couch had no thorns in it that night; my solitary room no fears. At once weary and content, I slept soon and soundly; when I awoke it was broad day.

– Charlotte Bronte

Jane Eyre, Chapter 11. On arriving at Thornfield at night Jane has been warmly greeted and shown to her room by the housekeeper Mrs. Fairfax. As she starts this new chapter in her life, Jane feels safe and secure and protected in Thornfield mansion. When she says her couch has no thorns in it, this a metaphor suggesting that she slept comfortably and soundly.