Author Randy alcorn, answers the question, "Why did you write books on Heaven?" From an interview with Tyndale Publishers.

Several people have already asked about my response to the passage of the Health Care Reform Bill and its inclusion of abortion. Yes, I am deeply concerned about its effect on unborn children. However, even though this bill has passed, the righteous cause of the unborn is not over. 

Consider the fantastic words contained in Romans 8:19-23: The sufferings of this present time are not worthy to be compared with the glory that will be revealed in us. The creation waits in eager expectation for the sons of God to be revealed. For the creation was subjected to frustration [curse]... in hope that the creation itself will be liberated from its bondage to decay and brought into the glorious freedom of the children of God....We know that the whole creation has been groaning as in the pains of childbirth right up to the present time. Not only ...

As I say in the introduction to Heaven, readers should carefully examine God’s Word and evaluate the book’s claims accordingly (Acts 17:11). If they do, I believe they will discover that the great majority of the book is solidly grounded in Scripture.

Some of the portrayals of Heaven in my novels Deadline and Dominion are surprising and unconventional.

Much of the confusion about what will take place in heaven is because most people don't think of heaven as the "New Earth." It's on the new earth that we will do earthly things. Unless teaching and writing are evil (part of the curse) or scripture says there will be no teaching or writing on the new earth, then there will be. Human beings who have bodies do things to the glory of God such as eat, drink, talk, think, communicate, rest, work, etc. so there would be writing books, reading books and teaching.

We know by the context.

Author Randy Alcorn is quick to point out that the Bible tells us much more about Heaven than we might realize. In Light of Eternity (1999) was his first nonfiction book about Heaven and in it, he addresses all the questions above and a lot more – and it’s all just a re-telling of what Scripture says.

When we die we go to be with Christ (II Cor. 5:8) which is wonderful. But we are still incomplete, in a pre-resurrected state, anticipating Christ’s return to earth, and our resurrections. The place we’ll live forever will be where God comes down to dwell with us, on the New Earth (Revelation 21:1-3).