Before God ever asked Israel to accept His kingship, He proved Himself through action. The Mekhilta lays out the sequence with deliberate precision, and the order matters.
First, God took Israel out of Egypt. He shattered the most powerful empire on earth to free a nation of slaves. Then He split the sea, turning an impassable barrier into dry land while the pursuing Egyptian army drowned behind them. He brought down manna from heaven — bread that appeared fresh every morning on the desert floor, feeding an entire nation in a place where no food could grow. He raised the miraculous well of Miriam, a source of water that followed the Israelites through the wilderness. He sent quail when they craved meat. And He waged war against Amalek, the first nation to attack Israel after the Exodus.
Only after all of this — after liberation, miracle, sustenance, water, food, and military protection — did God say to them: "I will rule over you."
And they responded: "Yes! Yes!"
The double affirmation is not accidental. The Mekhilta presents a model of legitimate sovereignty. A ruler does not demand allegiance first and deliver benefits later. God demonstrated His worthiness through deeds before asking for a single thing in return. The covenant at Sinai was not imposed on an unwilling people. It was offered to a nation that had already witnessed, firsthand, what their King could do. Their "Yes!" was not coerced. It was earned.