Unto thee it was shewed. He first says that God had so proved His divinity by miracles and prodigies, that the Israelites might know certainly that He was God. Whence, too, he concludes that He is the only God; for although God's holy name be torn in pieces by various opinions, whilst each one manufactures his own gods for himself, yet is it still sure that the power and dominion of God cannot be withdrawn from Him, but reside in a single subject, as the logicians say. Therefore the essence of the one God overthrows and annihilates all the other deities which we foolishly invent for ourselves. And this we must carefully remark, for this has been the common error of all ages, to seek for a mixture of many gods, whereas all these imaginations should vanish before the brightness of the true God. In the following verse he confirms this declaration, because God instructed His people out of heaven, and in the fire. Is it, however, asked how these two points accord which seem to be opposed to each other, that God's voice was heard from heaven and from the midst of the fire? I reply, that Moses simply means that the voice which flowed out of the fire into the people's ears was distinguished by plain indications which proved it to be heavenly.

Unto thee it was shewed, that thou mightest (z) know that the LORD he [is] God; [there is] none else beside him.
(z) He shows the reason why God did these miracles.

Unto thee it was showed,.... What the Lord did in Egypt:
that thou mightest know that the Lord he is God, there is none else besides him; that he is the one only living and true God, and there is no other: this phrase is often used by the Prophet Isaiah, to express the same great article of faith.

Israel was made to see all this, that it might know that Jehovah was God (האלהים, the God, to whom the name of elohim rightfully belonged), and there was none else beside Him (cf. Deuteronomy 4:39, Deuteronomy 32:39; Isaiah 45:5-6).