SNAKE IN THE GRASS : First mentioned in Genesis: 49:17 “Dan shall be a serpent by the way, an adder in the path, that biteth the horse heels, so that his rider shall fall backward.”
The expression “snake in the grass” refers to someone or something that is sneaky, who gains what they want from subterfuge, from deceit. A treacherous being, especially one who feigns friendship. A concealed danger. A secretly faithless friend. Someone who appears friendly and likable on the surface but has hidden agendas and will do anything to get what they want. They usually manipulate and deceive others to achieve their goals.

SNAKE : “The horned snake, or κεράστης, is a small, dangerous, and venomous serpent. The simile is that of a small serpent disturbed, and suddenly with deadly fangs striking a horse from behind. Dan is dangerous to his foes by ambuscades, secret raids, and guerilla warfare; Judges 18:27. The mention of the horse and horseman indicates the more wealthy, warrior class of the enemy. The very poisonous horned serpent, which is of the color of the sand, and as it lies upon the ground, merely stretching out its feelers, inflicts a fatal wound upon any who may tread upon it unawares.” (Cambridge Bible)

ADDER : “An adder, שׁפיפוןshepipon — A cerastes, probably, or kind of horned serpent, of a subtle nature, which, according to Pliny, hides its whole body in the sand, showing only its horns to catch birds. Signifies the subtlety of that tribe, which should conquer its enemies more by craft than by strength or force of arms, and by art, and policy, and surprise, gain advantages against them, like a serpent suddenly biting the heels of a traveller. (Benson Commentary) Diodorus Siculus says, of this kind of serpents, that their bites are deadly, and being of the same color with the sand, few discern them, so that many ignorantly treading on them fall into danger unawares; (Gill’s Exposition)

EAGLE EYES : The eagle eye is among the sharpest in the animal kingdom, with an eyesight estimated at 4 to 8 times stronger than that of the average human. They have extraordinary vision which enable them to hunt for their prey more easily. An eagle is said to be able to spot a snake 2 miles away. As the eagle descends from the sky to attack its prey, the muscles in the eyes continuously adjust the curvature of the eyeballs to maintain sharp focus and accurate perception throughout the approach and attack.

DISCERNING OF SPIRITS : The spiritual gift of discerning of spirits is the God-given ability or enablement to recognize the source of spirits — whether they come from the Holy Spirit, angelic spirits, demonic spirits, or individual human spirits — which are behind different manifestations or activities. The gift of discerning of spirits is often interwoven with other manifestation gifts. For example, a believer operating in discerning of spirits may be simultaneously aware of the presence of a demon, know what to do about the situation, and begin to command it to come out of the person. Receiving the information about the demon and knowing what to do with it is similar to – and interwoven with – a word of knowledge and a word of wisdom, while casting out the demon can also be in the category of working a miracle (Mark 9:38-39) or healing (Acts 4:16). (Petra Church)

“You are nothing but SNAKES IN THE GRASS, the offspring of poisonous vipers!” Matthew 23:33 TPT
“Ye serpents, ye generation of vipers, how can ye escape the damnation of hell?” Matthew 23:33 KJV
(This name is given to them on account of their pretending to be pious, and very much devoted to God, but being secretly evil, At the heart, with all their pretensions, they were filled with evil designs, as the serpent was, Genesis 3:1-5.)

“Now the SERPENT was more cunning than any beast of the field which The LORD God had made. And he said to the woman, “Has God indeed said, ‘You shall not eat of every tree of the garden’? ” Genesis 3:1.

“You brood of VIPERS! How can you speak good, when you are evil? For out of the abundance of the heart the mouth speaks.” Matthew 12:34.

“The GRASS withers and the flowers fall, because the Breath of The LORD blows on them. Surely the people are grass. The grass withers and the flowers fall, but the word of our God endures forever.” Isaiah 40:7-8

“You will tread on the lion and COBRA; you will trample the young lion and SERPENT. Because he loves Me, I will deliver him; because he knows My name, I will protect him.” Psalm 91:13-14

“And He said to them, “I saw Satan fall like lightning from heaven. Behold, I give you the authority to trample on SERPENTS and scorpions, and over all the power of the enemy, and nothing shall by any means hurt you.” ” Luke 10:18-19

“Therefore God exalted Him to the highest place and gave Him the name above all names, that at the name of Jesus every knee should bow, in heaven and on earth and under the earth, and every tongue confess that Jesus Christ is Lord, to the glory of God the Father.” Philippians 2:9-11.

“Behold, I am sending you out like sheep among wolves; therefore be as shrewd as SNAKES and as innocent as doves.” Matthew 10:16

“But strong meat belongeth to them that are of full age, even those who by reason of use have their senses exercised to DISCERN both good and evil.” Hebrews 5:14.

“Set your minds on things above, not on earthly things. For you died, and your life is now hidden with Christ in God.” Colossians 3:2-3.

“But the manifestation of the Spirit is given to every man to profit withal. For to one is given by the Spirit the word of wisdom; to another the word of knowledge by the same Spirit; To another faith by the same Spirit; to another the gifts of healing by the same Spirit; To another the working of miracles; to another prophecy; to another DISCERNING OF SPIRITS; to another divers kinds of tongues; to another the interpretation of tongues: But all these worketh that one and the selfsame Spirit, dividing to every man severally as He will.” 1 Corinthians 12:7-11.

“And war broke out in heaven: Michael and his angels fought with the dragon; and the dragon and his angels fought, but they did not prevail, nor was a place found for them in heaven any longer. So the great dragon was cast out, that SERPENT of old, called the Devil and Satan, who deceives the whole world; he was cast to the earth, and his angels were cast out with him. Then I heard a loud voice saying in heaven, “Now salvation, and strength, and the kingdom of our God, and the power of His Christ have come, for the accuser of our brethren, who accused them before our God day and night, has been cast down.” And they overcame him by the blood of the Lamb and by the word of their testimony, and they did not love their lives to the death. “ Revelation 12:7-11.