The passover lamb represents communion, deliverance from bondage, Christ the lamb of God offered for our deliverance from bondage . Bitter herbs represents the suffering, the trials associated with identifying with Christ the word. It represents sufferings, trials, tribulations and temptations through the journey before them. It meant in type that they were going to meet hostilities and many hindrances in the journey before them.
Meat, bread and bitter herbs are a type of a pertaking. The bread represents life while the bitter herbs represents suffering. This things were symbolic of the comings.
Israel is a type of the church, a type and antetype.
Revelation 10:9,10
9 And I went unto the angel, and said unto him, Give me the little book. And he said unto me, Take it, and eat it up; and it shall make thy belly bitter, but it shall be in thy mouth sweet as honey.
10 And I took the little book out of the angel's hand, and ate it up; and it was in my mouth sweet as honey: and as soon as I had eaten it, my belly was bitter
John 16:33
33 These things I have spoken unto you, that in me ye might have peace. In the world ye shall have tribulation: but be of good cheer; I have overcome the world.
1 Corinthians 5:7
7 Purge out therefore the old leaven, that ye may be a new lump, as ye are unleavened. For even Christ our passover is sacrificed for us:
John 16:33
33 These things I have spoken unto you, that in me ye might have peace. In the world ye shall have tribulation: but be of good cheer; I have overcome the world.
The revelation symbolism of the bitter herbs can best be understood in these words:
Philippians 3:7-11
7 But what things were gain to me, those I counted loss for Christ.
8 Yea doubtless, and I count all things but loss for the excellency of the knowledge of Christ Jesus my Lord: for whom I have suffered the loss of all things, and do count them but dung, that I may win Christ,
9 And be found in him, not having mine own righteousness, which is of the law, but that which is through the faith of Christ, the righteousness which is of God by faith:
10 That I may know him, and the power of his resurrection, and the fellowship of his sufferings, being made conformable unto his death;
11 If by any means I might attain unto the resurrection of the dead
By choosing to identify with Christ, the Pascal lamb, the Christian is identifying with his suffering:
For the picture of him is given thus in the scripture:
Isaiah 52:13-15
13 Behold, my servant shall deal prudently, he shall be exalted and extolled, and be very high.
14 As many were astonied at thee; his visage was so marred more than any man, and his form more than the sons of men:
15 So shall he sprinkle many nations; the kings shall shut their mouths at him: for that which had not been told them shall they see; and that which they had not heard shall they consider
Isaiah 53:1,3,5,7,10,11
1 Who hath believed our report? and to whom is the arm of the LORD revealed?
3 He is despised and rejected of men; a man of sorrows, and acquainted with grief: and we hid as it were our faces from him; he was despised, and we esteemed him not.
5 But he was wounded for our transgressions, he was bruised for our iniquities: the chastisement of our peace was upon him; and with his stripes we are healed.
7 He was oppressed, and he was afflicted, yet he opened not his mouth: he is brought as a lamb to the slaughter, and as a sheep before her shearers is dumb, so he openeth not his mouth.
10 Yet it pleased the LORD to bruise him; he hath put him to grief: when thou shalt make his soul an offering for sin, he shall see his seed, he shall prolong his days, and the pleasure of the LORD shall prosper in his hand.
11 He shall see of the travail of his soul, and shall be satisfied: by his knowledge shall my righteous servant justify many; for he shall bear their iniquities.
Bitter herbs therefore is a symbolism of the sufferings and reproaches one goes through in identifying with God, the light.