I haven't previously read anything by Charles ('Chuck') R Swindoll, although I had heard of him as a sound American evangelical paster, fairly elderly by now. I believe this book was part of the inspiration for Philip Yancey's excellent and popular 'What's so Amazing about Grace?'
'The Grace Awakening' is a bit heavier going; the early chapters cover similar ground to Yancey's, pointing out what a lack of grace there is in so many Christians and church teaching. He distinguishes vertical grace - that which God extends to us - and horizontal grace - that which we extend to each other.
He also shows the danger of 'grace killers': those who are so insecure or immature in their faith that they not only live by a rigid set of rules, but try to insist that others do the same. I haven't really come across many of these in the UK; we tend much more towards apathy and grey areas than black-or-white fundamentalism. But in the USA and elsewhere in the world (including the UK, if you look hard enough) there are plenty of people whose lives are bound up with rules and petty legalism.
Of course, extending grace to everyone means we let go not just of our friends and relatives, but also of other Christians we disagree with, including the legalists. Horizontal grace means that we simply love them, and allow God to deal with them in his own way, recognising a wide variety of tastes, doctrines and persuasions within the Body of Christ.
The book is divided into fourteen chapters, and I found the later ones quite thought-provoking. Swindoll challenges his readers to show grace in the workplace, the world, and in our marriages. He shows many Scriptural examples of those to whom God extended grace, and encourages us to use our freedom wisely and non-judgementally.
Highly recommended; preferably read this over a week or two, taking a chapter at a time. Written in 1990 but still in print in both UK and USA.