The love and reverence for Jewish books is seen in Jewish law. It is not permissible for a sacred Jewish text to lie on the ground and if by accident a book is dropped to the floor it should be picked up and given a kiss. A Jewish book is not to be left open unless it is being read, nor is it to be held upside down. It is not permitted to place a book of lesser sanctity on top of a book of higher holiness, so for example one must never place any book on top of the Tanakh. If one says to someone, "Please hand me this book," the book should be given with the right hand and not with the left hand." If two men are walking and one who is carrying a sacred books should be given the courtesy of entering and leaving the room first, as the second is enjoined to pursue knowledge." Rabbi David ibn Zimra of the 16th century comments that "if one buys a new book he should recite the benediction of the She-Heheyanu."