Clint Archer asks and answers the question, "Why Preach the Older Testament?" here. This is a much better approach than the one advocated recently by a well-known pastor who advocates unhitching the Old Testament from the New. In any case, Clint's four points are as summarized as follows.
1. The Old Testament, like the New Testament, is inspired and profitable.
2. The Old Testament elucidates understanding of the New Testament.
3. The Old Testament has been given as an example for New Testament believers.
4. The Old Testament elaborates on ethics omitted in the New Testament.