Is the God of the Old Testament Different than the God of the New Testament?

When we look deeper, the answer is clear

Many operate under the assumption…There’s the Old Testament God who commanded holy war and swallowed up the disobedient with fire and earthquakes. And then there’s the God of the New Testament, a God of love, mercy, and grace. David Platt — Radical

The above statement made me curious and to be honest, a bit nervous. I’ve never thought of the God of the Old Testament as different than the God of the New Testament. I knew situations and people were different in the two Testaments, but my understanding has always been that God is the same yesterday, today, and tomorrow. To think the God I love could change was very unsettling for me. I had to investigate this possibility further.

For I the Lord do not change; (Malachi 3:6, NIV)

Fact №1 — The immutability of God

We can’t fit God into any kind of container. That would mean confining or shaping Him into something, and that’s impossible. God is immutable, unchanging over time and unable to be changed!

Every good gift and every perfect gift is from above, coming down from the Father of lights, with whom there is no variation or shadow due to change. (James…