“Hello, I’m a Christian and I was asked the following question: [Why] does the angry God of the Old Testament kill children and carry out massacres? I would be grateful if you could help me. May God be with you” 

Answer:

We answer this question in two steps:

In a first step we have to clarify in which way the bible makes anthropomorphous statements about God, in other words, uses anthropomorphisms.  Anthropomorphous statements about Gods are statements which address God as if he were a human being.  According to such statements God has a face, eyes, ears, arms, feet, insides, heart, a back etc.; he stands, walks, sits, sleeps, awakes, comes etc. Such statements also include anthropophathic statements, for example that God loves, hates, is angry, smiles, regrets, forgets and is jealous. Where in the Old Testament and to a lesser extent in the New Testament is presented with human imagery the Bible follows the language of ancient religions. Unlike the myths of the ancient Orient and the Greek gods the Bible avoids any sexual references in connection with God: He is not a father or a spouse in the physical sense.

Josef Schreiner writes: “Anthropomorphisms [i.e. anthropomorphic language] about God are not an error that should be avoided, because as with other abstract expressions (such as spirit, being etc.) without theological concerns, it is only possible to use the language and expressions of human beings. They would present a danger to our understanding of God if they were naively considered to be adequate statements about God so that he appeared to be like a human being. But the bible rejects such interpretations: On God’s mountain Israel did not see a figure but only heard the voice of Yahweh, the thunder, to be precise (Deuteronomy 4:12): It is therefore not allowed to make for itself an image of God (verses 15ff). God does not live in a house like a king (1 Kings 8) [...] in truth, God cannot be compared to anyone [Isaiah 40:25), he is a hidden God (Isaiah 45:15). That people are created in the image of God (Genesis 1:26) and as stewards of creation does not mean that God has a human form, nor does the prohibition to make images of God in the book of Deuteronomy, which is aimed against idolatry, imply a prohibition of anthropomorphisms. [...] In the bible anthropomorphisms have a deeper meaning and are of major importance: They describe God as a living being, as someone who turns towards the world and towards people, who seeks community with people, personally grants salvation and requests obedience.” (Josef Schreiner , art. Anthropomorphismus. I. Biblisch., Lexikon für Theologie und Kirche. 3, edition, Vol 1, column 734-735, quotation: column 735.)    

In a second step we reflect biblically and theologically on God’s wrath. To this end we follow the explanations by Renate Brandscheidt, with a few small omissions and stylistic changes. (Art. ‚Zorn Gottes‘ (Wrath of God) in: Lexikon für Theologie und Kirche, 3. Edition., Vol. 10, columns 1489-1490) 

Many statements about the wrath of God in Holy Scripture describe God’s dislike of all things evil (Amos 1:2). They are aimed at those who have violated the Covenant (Hosea 8:1-14) and who suppress the truth (Romans 1:18). They show that although the wrath of God is occasionally seen as mysterious [...], it is neither a case of raging vengeful despotic capriciousness, nor of a demonic evil power [...] but of the manifestation of God’s holiness and the enforcement of his absolute claim to power (Psalm 5:5ff; Ephesians 5:1-6). This shows that we must not rationalise the wrath of God to a rigid doctrine of revenge (Job: speeches of his friends) or characteristic of God. In his wrath God reacts to where people have deficiencies and to the human hubris of individualism and making themselves the sole standard of everything.  Furthermore, God’s wrath is not only expressed in individual acts of revenge but also in the comprehensive threat arising from humanity and their world (Isaiah 13:13; 34:1-4; Hebrews 10:31) It points to the break between God and humanity which according to Genesis is connected with mankind’s falling away from the direction of God-willed development (Genesis 3). The wrath of God therefore includes the whole world of transient humanity (Psalms 90:9-12; 102:11 ff) and turns this time into a period of judgement (Isaiah 26:20 f; Matthew 3:7; Ephesians 2:3), in which God can be seen as the cause for every mishap (Amos 3:6). Because for the creator God everything earthly can be a tool for wrath, believers often feel that they are exposed to disaster without any defences (Job 16:9 ff; 19:11, Jeremiah 3; Maccabees 1:54-64). But God’s anger with human sin will not go as far as destroying all of creation, because of God’s change of heart about his own judgement and the affirmation of his creation (Genesis 6:6; 8:21f). Ultimately, God is always the God of our salvation. His patience prevents the outpouring of his anger and postpones the final judgement (Exodus 32:13; Jeremiah 18:8; Amos 7:3,6) and thus provides space for repentance and conversation (Jeremiah 26:3 .. 13; Jonah 4;2; Peter 3:9). And so the righteous can be purified while sinners are warned (Job 33; 36:1-14). Only a refusal to repent (1 Peter 3:20) makes God’s wrathful judgement inevitable and points to the day of Yahweh's judgment, the day of wrath, which brings the final reckoning and the ultimate day of judgement. [...]

According to the New Testament the eschatological revelation and visible embodiment of God’s saving will that surrounds his wrath is Jesus Christ (John  3:16; Romans 5:8-10; 9:22ff). Christ is the fulfilment of the law (Romans 3:25ff), the true meaning of this is recognised and upheld in the New Covenant (Romans 3:21). And so the law itself can no longer determine God’s relationship with humanity, rather, where it does continue to determine that relationship it arouses God’s wrath (Romans 4:15). In Christ humanity is divided into those who are freed from the wrath of God because they allow themselves to be saved through his mercy (John 5:24, 1 Thessalonians 5:9) and those who reject Christ the Saviour and remain under God’s wrath. (Matthew 3:7ff; 25:41; John 3:36).

For the theologian Hans Urs von Balthasar the wrath of God describes God’s reaction to the human sin Christ has borne on behalf of humanity. According to Balthasar’s consistent dramatic view Christ proclaimed a God who is never angry and who meets sin with forgiving love. But the words of judgement show that sinful humanity prefers to lock itself into a world that is remote from God and that it is therefore only capable of experiencing God as angry. Because all people, including believers, remain part of sinful humanity the topic of divine wrath never loses its importance (see Raymund Schwager „Zorn Gottes, II. Systematisch-theologisch“ in: Lexikon für Theologie und Kirche, 3. Edition, Vol. 10, column 1490.)