Tremble, O earth, at the presence of the Lord

Psalm 114
When Israel came out of Egypt, the house of Jacob from a people of foreign tongue, Judah became God's sanctuary, Israel his dominion.
The sea looked and fled, the Jordan turned back; the mountains skipped like ram, the hills like lambs.
Tremble, O earth, at the presence of the Lord, at the presence of the God of Jacob, who turned the rock into a pool, the heard rock into springs of water.
This is the festival which marks the escape from Egypt at the exodus. The people remember how God freed them when they were slaves and made them his own people.
Why?
For the great of the Lord did for Israel, his people, so the mountains skipped like ram.
All the earth tremble before the Lord so people have to fear at the presence of the Lord either.
How?
Remember what God have done for us! Remember God's grace and love to me and fear God's holy name!