23 “So if you are presenting a sacrifice[h] at the altar in the Temple and you suddenly remember that someone has something against you, 24 leave your sacrifice there at the altar. Go and be reconciled to that person. Then come and offer your sacrifice to God.
Matthew 5:23-24
To come into the presence of God in worship was a serious affair. It was not like our Sunday mornings where you can just rock up and start to worship. Before entering the Temple, many Jews would undergo a ritual bath in a mikveh—a pool of clean, gathered water. This wasn’t about hygiene, but about becoming ritually pure (tahor). This was essential for entering holy space or offering a sacrifice. While they travelled to the temple people would avoid anything that would make them unclean. This would be things like touching corpses, eating certain foods or even being around certain people (e.g. gentiles, lepers). The sacrifice itself would also be examined for blemishes. It was to be pure and perfect for God to receive.
People would prepare everything so that God would look favourably on their offering. However, Jesus wants their holiness to not just be skin deep. If God hates anger, then we should resolve our relationships between each other before we come to receive forgiveness from him. If God will punish anger then we can not come to worship him with grudges unresolved.
Can you imagine how this idea would change the world! If every Christian resolved every broken relationship they have before they came to worship God. No anger would last more than a week. Relationships would be restored before bitterness could take root. The community of God would share the love of God.