Jesus said that He was with the Father before the Creation ....
John 17:5 And now, Father, glorify Me in Your presence
with the glory I had with You before the world existed.
Yeshua is said to be the Lamb which was slain from the foundation of the world (Revelation 13:8), yet we have the Bible also saying,
“Nor yet that he should offer himself often, as the high priest entereth into the holy place every year with blood of others; For then must he often have suffered since the foundation of the world: but now once in the end of the world hath he appeared to put away sin by the sacrifice of himself.” (Hebrews 9:25-26)
Clearly, the Hebrews passage states that Yeshua was not literally slain from the foundation of the world, but rather must have been slain in the mind or plan of Almighty Yahweh, before the foundation of the world. This is akin to John 1:1 which speaks of the very word of Elohim, being with Elohim in the beginning. This spoken word, or plan of Yahweh, existed throughout the eons of time. From the beginning of time, Yahweh had Yeshua’s sacrifice in His plan for all humankind, for it was through Yeshua that we would receive our justification (Romans 4:25).
1 Peter 1:18-20 continues to explain this by saying:
"Forasmuch as ye know that ye were not redeemed with corruptible things, as silver and gold, from your vain conversation received by tradition from your fathers; But with the precious blood of Christ, as of a lamb without blemish and without spot: Who verily was foreordained before the Did Yeshua Pre-exist? 129 foundation of the world, but was manifest in these last times for you."
Notice the use of the word foreordained. Yeshua was foreordained from the foundation of the world, but was made manifest or revealed in these last times. He did not exist as a person or being in former times, but in these last times Yahweh allowed him to be born of a woman (Galatians 4:4) and speaks through him (Hebrews 1:1-2).
It is especially intriguing to find Yeshua praying to the Father, that He would let the disciples share in this glory, (John 17:24) and then he, in turn, mentions the foundation of the world. The disciples would indeed share in the glory of the crucifixion by having their sins washed away, but they definitely did not share Yeshua’s glory by themselves being involved in a Trinitarian being. The glory that Yeshua had was as the slain lamb of Yahweh, in the mind of Yahweh, and Yeshua was praying for that glory to be brought about literally, so as to give unto all those who would accept, eternal life. This is why Yeshua began in John 17:1-2 by saying,
“These words spake Yeshua, and lifted up his eyes to heaven, and said, Father, the hour is come; glorify thy Son, that thy Son also may glorify thee: As thou hast given him power over all flesh, that he should give eternal life to as many as thou hast given him.”
Yeshua wanted to bring about the fruition of eternal life, by Yahweh, glorifying him as the ultimate sacrifice, and Yeshua, in turn, glorifying the Father.