Karpas: One dips green vegetables in salt water to symbolize that like karpas, we must undergo an entire immersion of one's body for the purpose of a complete purification. One should not be like the person who immerses himself with an impure reptile in his hand, God forbid! This is an allusion to the fact that the Israelites were idolaters while they were in Egypt. When God took them out of Egypt in order sanctify them by giving them the Torah, it was necessary first to remove the impurity that was upon them and to have them perform complete repentance. One immerses the greens to symbolize the Baal Teshuvah (repentant) who is as humble as the plants in the field which are trampled underfoot. The greens are called karpas, which comes from the word for trampled over; or it is related to the word refes, spelled with a shin instead of a samech, which is the word for mud or earth. (See Rashi in Proverbs, 6) Karpas is a reminder that the Israelites were humiliated by the Egyptians; they were like "mud and dirt." The combination of the words rehatz and karpas also hint at the process of purification: first cleansing oneself, then immersion and finally 'sprinkling,' as we find in the law of the red heifer: the sprinkling of the ashes of the red heifer mixed in water was done with a bunch of hyssop. (See Nu.19:18) Here we dip a bunch of greens as an allusion to this ritual of purification. Similarly, the people were commanded in Egypt to dip some greens in the blood of the Passover lamb and to place the blood on the lintel and the doorposts of their homes, as it says, You shall take a bunch of hyssops.." (Ex. 12:22) Another reason for dipping: Having preparing himself to go before the King, he now shows his allegiance and his willingness to obey the King's command. By dipping the greens in salt water or vinegar, he still remembers the time when he was humbled while in Egypt and that God took us out of subjugation so that we could reach this exalted level. The dipping of karpas alludes to two opposing ideas, subjugation and freedom. First it symbolizes subjugation when our lives were like the vinegar or the salt water, and in the end it symbolizes the merit of dipping the hyssop when we fulfilled the commandment of placing the blood on the doorposts of our homes, so that Israel was saved from the death of the first born and afterwards they went forth to freedom.

Karpas is a code word for subjugation, which we learn by reading the word backwards; ס' פרך – the letter samech followed by the word parech (oppression). This means that sixty (number value of samech) ten-thousands were forced to do oppressive labor. (Ex. 13) Another way that I interpret this word is as an abbreviation, both forward and backwards. פנים– כרבוא פעמים ס' ,אחור– סופם פרך First they were a people of sixty thousand; afterwards they were oppressed. פנים. כלו רעמסס פתום ס ' רבוא -- אחור ס' רבוא פתום רעמסס כלו Another interpretation: read forward: sixty thousand finished the city of Ramses and Pitom and read backwards: sixty thousand finished Pitom and Ramses. בתחילה ס' רבוא פה רך אבל סוף פרך Yet another allusion in the word karpas: In the beginning there were sixty thousand who were enticed by soft words. In the end sixty thousand were oppressed. (the words for soft word Peh rach and the word for oppression - parech - are the same Hebrew letters). Let Me Explain: Rabbi Bondi finds several different ways of interpreting the dipping of the Karpas in salt water or vinegar.

1. The dipping symbolizes the process of teshuvah. It had to be a complete and unadulterated immersion. Rabbi Bondi uses the expression, immersing oneself with a reptile in his hand. Obviously if one does this, one is not purified by the immersion since the reptile is impure - is a useless act. Following on Kadesh and Rehatz, all three of these terms are types of purification. One must conduct ones immersion with humility just as the greens that one immerses are humble plants of the field.
2. Picking up on the theme of humility, the author suggests that the karpas is actually ki-refesh, 'like mud,' an allusion to how the Egyptians treated the Israelites. We are not only humble in the presence of God like the greens but we were humiliated by the Egyptians when we were slaves in Egypt.
3. The karpas is connected with the tenth plague - the death of the first born and the Passover offering. It is also an allusion to the hyssop plants which were immersed in the blood of the paschal lamb and they brushed against the doorposts of the house on the night of the tenth plague.
4. By performing this act at the beginning of the Seder, we are showing God that we have not forgotten how he redeemed us from Egypt and we are also showing that we faithfully followed His instructions by killing the lamb and dipping the hyssop in its blood which was then placed on the doorposts of the house.
5. Finally, Rabbi Bondi plays with the letters of the word karpas, suggesting that it contains the entire story of the Exodus from subjugation to freedom. He reads the letters both backwards and forwards (and from the inside out) finding hidden messages in these words. Unfortunately, there is no way to capture the cleverness of these different abbreviations.

The Tenth Plague is Central The redemption from Egypt was fulfilled through the plague of the first born; this was also the first warning that God gave to the Egyptians. (See Ex. 4:22-24, "Thus says the Lord: 'Israel is my first born. I have said to you, Let My son go that they may worship Me; Yet you refuse to let them go. Now I will kill your first born.'") The reason for this is that the purpose of the redemption from Egypt was to make known and publicize the power and unity of God in the world. (This could only be accomplished by striking down the first born.) Egypt was mired in idolatry, the oldest Egyptians claiming they were gods. As a result, Egyptians who were younger could never boast to those who were older than them they were gods. Their elders had witnessed with their own eyes that they were born of a mortal women from a putrid drop of semen. The elders, on the other hand, could deceive those who were younger as well as their own children with false oaths and lies claiming that they were gods and that they had created themselves, just as Pharaoh said about himself. Therefore, when God struck down the first born, even the firstborn of every household, they had to admit that there is no God but the God of Israel, blessed be God's name. This is stated in the Talmud: When the holy one took vengeance on the whole nation and punished its gods. (See Rashi, Ex. 11:5)