The second of the O Antiphons.

O Adonai,
et dux domus Israel,
qui Moyse in igne flammae rubi apparuisti,
et ei in Sina legem dedisti:
veni ad redimendum nos in brachio extento.

In English:

O Adonai,
And leader of the house of Israel,
Who appeared to Moses in the burning bush,
And on Sinai gave him the law,
Come to redeem us with outstretched arm.