What may we know? We often ask this question with hope that is tremulous--or it may be with tremulousness that is hopeful. What may we know? Certainly not all that we sometimes wish to know; but then we sometimes wish to know things the knowledge of which would be useless, or curious, or beyond our reach until we can see with tearless eyes, and realise with sinless hearts. There are certain aspects under which heaven seems to be altogether visionary. Where is it? We are not told. What are the dimensions and outlines of it? We do not know. It is described under a great variety of material figures. We read of its gates of pearl, its walls of jasper, its streets of gold, its river of the water of life, its tree of life; but we know that these descriptions symbolise the spiritual. Not that they are mere riddles, however. Some of their truth may be confidently guessed. There is one important fact of which we cannot be in doubt. Heaven is the place in which will be developed and perfected a certain character--certain moral and spiritual qualifications. Heaven is where perfect goodness is, just as on earth happiness is where godliness and Christlikeness are. We may, therefore, put heaven where we will, and think about it almost as we please, provided we put the right sort of character there, and remember what sort of discipline here must prepare for it. This is the essential point in the revelations of this book: "There shall in no wise enter into it anything that defileth, neither whatsoever worketh abomination, or maketh a lie: but they which are written in the Lamb's book of life." There _must_ be a heaven for the good.