Deuteronomy 32

Deuteronomy 32:9:
But the Lord's portion is his people, Jacob his allotted heritage.

-First, by His own sovereign election. He chose them, and set His love upon them. He chose them altogether apart from any goodness in them at the time, or any goodness which He foresaw in them. He had mercy on whom He would have mercy, and ordained a chosen company unto eternal life. Therefore, are they His by His unconstrained election.

They are not only His by choice--but by purchase. He has bought and paid for them to the utmost farthing--hence there can be no dispute about His title to them. The Lord's portion has been fully redeemed, not with corruptible things, as with silver and gold--but with the precious blood of the Lord Jesus Christ! See the blood-mark upon all the elect, invisible to human eye--but known to Christ, for "the Lord knows those who are His!" He forgets none of those whom He has redeemed! He counts the sheep for whom He laid down His life, and well remembers the people for whom He gave Himself.

They are also His by conquest. What a battle He had in us--before we would be won! How long He laid siege to our hearts! How often He sent us terms of surrender! But we barred our gates, and fortified our walls against Him. Do we not remember that glorious hour--when He conquered our hearts? When He placed His cross against the wall, and scaled our ramparts, planting the blood-red flag of His omnipotent mercy on our strongholds? Yes, we are, indeed--the conquered captives of His omnipotent love!

--Charles Spurgeon

Deuteronomy 32:33:
Their wine is the poison of dragons, and the cruel venom of asps.

The word serpent appears twenty-four times in twenty-three verses in the Christian Standard Bible (CSB). Ten applications are clear references to Satan (Gen. 3:1, 2, 4, 13, 14; 2 Cor. 11:3; Rev. 12:9, 14, 15; 20:2). Three times serpent appears in the confrontation between Moses and the magicians of Pharaoh’s court (Exod. 7:9, 10, 12). Three references are to a sea serpent or Leviathan, a mystical deity over which the Lord has absolute power (Job 26:13; Isa. 27:1; Amos 9:3).
Twice, there are mentions of a “flying serpent,” either an analogy of Assyria (Isa. 14:29) or a reference to one of the wild beasts in the Negev (Isa. 30:6). Singular references include: an analogy of an enemy’s wine (“serpent’s venom,” Deut. 32:33); a place (“Serpent’s Well,” Neh. 2:13); predators who lie in wait (Ps. 91:13); animal food in the new creation (“the serpent’s food will be dust!” Isa. 65:25); and Jesus’ instructions to his disciples to take prudent action in light of coming persecution (Matt. 10:16; cf. 21-23).
Old Testament writers use three different Hebrew words translated “serpent” in these passages. The most common is nachash, meaning “serpent” or “snake.” The word even makes a hissing sound when spoken. The word tanniyn (used in Exod. 7; Deut. 32:33; Neh. 2:13; and Ps. 91:13) has a broader application and can mean “serpent, venomous snake,” “sea or river monster,” or “dragon or dinosaur.” The third word, saraph, is used only once (Isa. 30:6) and may be translated “serpent,” “fiery serpent,” or “poisonous serpent.” It’s also the word from which we get seraphim, the six-winged heavenly creatures Isaiah sees above the throne in his vision of God (Isa. 6).
In the CSB New Testament, the Greek word ophis is used more than a dozen times and is translated “snake” or “serpent.” It may refer to an actual snake (Matt. 7:10; John 3:14-15; cf. Num. 21:8-9), or it may be used figuratively to illustrate certain traits or qualities. For example, Jesus calls the scribes and Pharisees “snakes” because of their venomous hypocrisy (Matt. 23:33). After sending his disciples to proclaim the gospel, Jesus tells them to be “as shrewd as serpents and as innocent as doves” (Matt. 10:16).
Other references are directed more toward the demonic realm. Believers are promised authority over snakes, demonstrating their power over Satan and his agents (Luke 10:19). And Paul warns the Corinthians that the ancient serpent continues to strike with lethal intent: “But I fear that, as the serpent deceived Eve by his cunning, your minds may be seduced from a sincere and pure devotion to Christ” (2 Cor. 11:3).
As you can see, the writers of Scripture employ numerous Hebrew and Greek terms to depict a variety of creatures associated with serpents. Andrew Naselli notes that serpent is an umbrella term – a “big category” – that includes both snakes and dragons. Further, he writes that a serpent has two major strategies that become evident in Scripture: to deceive and devour:
As a general rule, the form a serpent takes depends on its strategy. When a serpent in Scripture attempts to deceive, it’s a snake. When a serpent attempts to devour, it’s a dragon. Snakes deceive; dragons devour. Snakes tempt and lie; dragons attack and murder. Snakes backstab; dragons assault.
The Serpent and the Serpent SlayerFor our purposes, we focus primarily on depictions of Satan as the serpent in Genesis and Revelation. --Rob Phillips; What Every Christian Should Know About Satan; High Street Press (August 20, 2021)

Deuteronomy 32:35:
To me belongeth vengeance and recompence; their foot shall slide in due time: for the day of their calamity is at hand, and the things that shall come upon them make haste.

Jonathan Edwards: In this verse is threatened the vengeance of God on the wicked unbelieving Israelites, who were God's visible people, and who lived under the means of grace; but who, notwithstanding all God's wonderful works towards them, remained (as ver. 28.) void of counsel, having no understanding in them. Under all the cultivations of heaven, they brought forth bitter and poisonous fruit; as in the two verses next preceding the text. The expression I have chosen for my text, Their foot shall slide in due time, seems to imply the following doings, relating to the punishment and destruction to which these wicked Israelites were exposed.
That they were always exposed to destruction; as one that stands or walks in slippery places is always exposed to fall. This is implied in the manner of their destruction coming upon them, being represented by their foot sliding. The same is expressed, Psalm lxxiii. 18. "Surely thou didst set them in slippery places; thou casted them down into destruction."

Deuteronomy 32:46-47:
Set your hearts on all the words which I testify among you today, which you shall command your children to be careful to observe--all the words of this law. For it is not a futile thing for you, because it is your life, and by this word you shall prolong your days in the land.

Moses’ warning to the Israelites 3,500 years ago, regarding the critical importance of God’s law in their possession of the land of Canaan, applies to America today.