This is not a new question
Of course, if you're Jewish, there's no inconsistency of this kind at all. However, there are distinct traditions even within that relatively unified body of work, also known as the "Tanach" for its rather natural division into the Torah (the first books dealing with law), the Prophets, and the Hagiographa. The book of Job, for example, is a retelling of an ancient Hebrew/Semite myth and is hard to reconcile with later theology. Also consider the prophets, such as Isaiah, who speak of a God who chokes on the stench of burnt offerings. This same God authorizes burnt offerings in the Pentateuch.
If you're a Christian, you notice that the New Testament doesn't deal with God in the same way. In the OT, the children of Abraham have a close personal relationship with God, who tends to speak to them in very direct ways. In the NT, you get God's son and emissary, who calls all peoples to obey the same commandments, but jimmies the emphasis a little. In any event, if you believe that the book of Revelation presents an accurate view of the end of the world, you do get a lot of real OT "wrath-of-god type stuff...dogs and cats, living together...mass hysteria!"
The most interesting interpretation of this juxtaposition, in my view, is the product of Gnostic thought. They believed that the god of the OT was a false god, with names like Yaldabaoth, Saklas, and Samael the blind god. Jesus's role was to explain this and tell people how to bypass his false reality and return to the pleroma or "fullness" of the true God's presence.
Peoples grow, ideas change. Thus, the way you present information may change as well. The authors of the OT and NT belong to different ethnic groups and different periods of history. You can reasonably believe that they're presenting the same basic information in divergent ways that reflect their ways of thinking.