TL;DR - Brother Lawrence is a delusional quack, and this book can be made more bearable by pretending it's a comedy piece.
Let's just get this out of the way: Brother Lawrence had some good things to say. I think most books have at least something good that you can take away. His focus was on loving God more and constantly communing with Him. He made some good points.
However, this man appears to have two separate mouths that he's constantly babbling contradictions out of. He'll have two statements that are polar opposites on the same page. He must have been deaf, because if he could have heard what nonsense was spewing out of his mouth this work wouldn't exist to torture us today. I wonder how his work lasted this long. There are too many grievances to list in a review that I want to keep short, so I'll stay general. If you really wanna know, just read this book. It's around 100 pages, and if you treat it as a comedy piece, it helps make it worth your while.
Some of the statements he makes are absolutely blasphemous to Scripture. He constantly makes comments about abandoning "devotions" and making things simple. What he means by devotions is unclear, however, I'm inclined to believe it means scheduled prayer time, regular fellowship believers, and devotions in the morning/evening/whenever. He even goes so far as to say that he finds himself closer to God in his day-to-day life than he does when he engages in regular prayer time. I wonder if Brother Lawrence knew that Christ Jesus Himself needed to get away for private prayer time after his day-to-day life.
Also, he seems to forget that God is holy, and that he commands us to be as well. He blatantly advises Christians to just do whatever we can, and no matter how inconsistent or feeble our offerings are, God will accept them and say they are good enough. He seems to forget that God actually has standards. Yes, there is grace in abundance, but there are also standards we should strive to attain. Lawrence's writing is void of striving to reach these standards.
OH AND LET'S NOT FORGET THE COMMENTS HE MAKES TOWARD SICK PEOPLE, 'KAY? I dare him to tell my mother that her Multiple Sclerosis is a gracious and merciful gift toward God, and to just be happy about it all the time. I dare him to tell my diabetic uncle to abandon modern medicine and be completely trusting in God to heal him. I dare him to tell my aneurotypical and autoimmune disease people to thank God for their crushing anxiety, discrimination, and incredible struggles that they need to thank God because their sickness brings them closer to God than anyone else when SOMETIMES THEY DON'T EVEN HAVE THE STRENGTH TO PRAY!
Brother Lawrence is only half the book, y'all. The other half is this Frank guy that I didn't even bother to read once I realized he wrote a book about being a "modern Mystic" 0_O
Yeah. I've only briefly touched on the numerous things wrong with this book, so if you take anything from this review, just know that Brother Lawrence is the sweetest most encouraging delusional quack out there.