Sapher (H5613) in Aramaic (used in Ezra and Daniel) means a document, letter, or written book. It is cognate with the Hebrew sepher (H5612, book/scroll) and relates to saphar (to count/recount/inscribe). It refers to official royal or legal documents.
Scripture itself is a divine document — God's written word to His people. The Mosaic law was recorded in a sepher. The 'Lamb's Book of Life' (sepher) contains the names of the redeemed (Revelation 20:15). Letters from divine authority carry binding power in Scripture, from the Mosaic covenant to the letters of the apostles. Writing itself is a sacred act of preserving and transmitting truth.