A lot of Christians will say, "God in the Old Testament was harsh, but he showed mercy in the New Testament" . There are many verses in the Old Testament where God openly displayed his wrath and made his wrath clear. And, when Jesus came he was that very same God but yet in the New Testmant he showed mercy and compassion to his sheep. But, here's the thing Jesus was just as critical as the God of the Old Testament when it came to the pharisees and the religious leaders of his day and quite frankly to the ungodly. In fact, whenever God had wrath and was angry its ALWAYS both Old and New Testament been towards the ungodly.
It's common for Pastors and Evangelists to say "God loves you" to the wicked and to the ungodly. But should this be the case? Because, scripture makes it clear that God despises the ungodly and this attitude continued in Christ. In fact, you can get any clearer than Psalm 11:5 where some English translations translates hate to abhors the wicked which is a much,much stronger word than just God hates the wicked.
So when a Pastor or an evangelist says to the wicked "God loves you" its actually factually incorrect if they are not among Gods sheep. But, also only God knows who his sheep are or evangelism would be extremely easy.
But what I'm mostly trying to start a debate on though is if God abhors the wicked, what else are we supposed to tell an unbeliever who potentially could be a sheep of God? So this problem spreads to call Christianity and not just the reformed community.
Yes, God loves all.
God IS love. This does not mean that "God is loving" to most or that God is mostly loving. God literally IS love. God's fundamental nature, his essence is love.
This is also why the Trinity is the central mystery of Christianity. This is why non-Trinitarian heresies are so fundamentally destructive.
God is not, by nature, a solitary being. If he were, love would not be part of God's nature. God is, by his very eternal nature, a relationship of love, Father, Son, and Holy Spirit. God's eternal nature is family and relationship.
Now, the difficulty that people run into is that they don't understand love, and what we call love, especially in this day and age is not love.
The first thing to understand is that love is NOT a feeling. The feeling that we call love is better called "affection". Affection leads us to love, but it in itself is not love and can become twisted so that it leads us away from real love as well.
The essential core of what real divine love is, is an act of will. Specifically Love is to will the good of the other, and especially to self-givingly, self-sacrificially will the good of the other.
The second thing to understand is that human affection and our experience of love are almost always experienced in combination with need. Almost all of the time, unless you specifically work to counteract it, our experience of loving someone makes us need them for our own emotional well-being. This also puts us in competition with them in a certain sense, because if I need a person, then my interests which depend on them, can come into conflict with their interests. Also, I it fosters attachment and dependence, which means I can't let them go, even if that's what is best for them.
Need is utterly and completely foreign to God. He has no need whatsoever. Jesus has experienced it as part of his human nature, but the Divine nature, by definition cannot have need.
Thus God's love has no slightest hint of need. He gains nothing if we love him, and loses nothing if we hate him. As such, he is never in competition with us because he needs nothing from us. He is perfectly free to act and will only for our best interests thus to love us perfectly.
The third thing to understand is that the emotions that we experience are almost all the result of the fact that we have a physical body with hormones and chemicals etc. God (except Jesus) does not have a physical body and as a result the "emotions" that are attributed to him in scripture such as wrath and love, are nothing like the way we experience those emotions. For us they are passions. The word passion means "suffering" and those emotions are called passions because we suffer them and they cause us suffering. They drive us through the experience of suffering.
God is not that way. He has no emotion in the sense that we experience emotions. Thus his wrath and anger are nothing like ours. The terms are only used in analogy. Just like God does not hate as we hate. When the Bible talks about God's wrath, or God hating, it cannot be understood in the context of how humans experience anger or hate etc.
Further, we know that God is not broken up into parts. He is all love. What this means is that his wrath and his love are the same thing. They are experienced differently by the people on the receiving end because of the choices those people made and what they became.
Imagine it like this... One person spends a great deal of time in very hot environments and as a result they become accustomed to heat. Those very hot environments become comfortable to them. Another person spends all their time in very cold environments, and as a result become accustomed to the cold. If you put that person into the hot environment they would find it unbearable, whereas the first person would hate the cold and prefer that same hot environment.
It is not the heat that is different, but how it is experienced by the people.
God loves everyone. Those who love God experience his love as paradise. Those who hate God experience is love as torment.
If you really delve into this logically and explore the philosophy of it you will find that even Hell is an expression of God's love and it exists because it is the best possible outcome for the people who go there.
Ultimately God holds that the highest good for all people is that they exist and to exist requires that they be free moral agents. As such God will allow people to freely choose self-destruction, but if they do choose self-destruction, they will make themselves miserable, and they will come to hate not only God, but themselves, and their own existence, to the point where existence itself is a torment to them. Thus even God's gift of existence, and self, which are expressions of his love, will become torment to them and seem like wrath and punishment.