I am angry at God - is that a sin

God is not fragile, and the Bible itself contains the prayers of furious, devastated believers - prayed at God, kept in his own book. Job accused God bitterly for chapters, and at the end God said Job had spoken to him while his tidy-answered friends had not (Job 42:7-8). David demanded 'How long wilt thou forget me, O LORD?

' (Psalm 13:1); Naomi renamed herself Bitter and said 'the Almighty hath dealt very bitterly with me' (Ruth 1:20); Jeremiah told God 'thou hast deceived me' (Jeremiah 20:7). What Scripture models is not polite distance but honest engagement - anger carried TO God rather than nursed against him from far away: 'pour out your heart before him' (Psalm 62:8). That is the difference that matters: the anger that stays in the conversation is the anger of faith; the anger that walks away and hardens is the danger (Hebrews 3:15).

So tell him exactly what you think - he already knows - and stay long enough to let him answer, as he answered Job not with explanations but with himself. Bring a wise believer into it too; anger at God is heavy to carry alone. He can take your worst prayer far better than your silence.