I have seen all the works that are done under the sun; and behold, all is vanity and a chasing after wind. That which is crooked can't be made straight; and that which is lacking can't be reckoned as straight. -- Ecclesiastes 1:15, RLIV.
And later he says:
Ecclesiastes 7:13 - Consider the work of God, for who can make that straight, which he has made crooked?
-- World English.
In other words, man, under the present sun of crookedness and vanity, cannot make himself straight; he cannot justify himself. Mankind came to be under this sinful, crooked condition when Adam sinned. Mankind has been in a dying condition ever since that disobedience. Since none could justify himself, none could be acceptable as a sacrifice to Jehovah to redeem mankind from his dying condition.
Psalms 49:7-9 - None of them can by any means redeem his brother, Nor give God a ransom for him. For the redemption of their life is costly, No payment is ever enough, That he should live on forever, That he should not see corruption.
-- World English.
Sinful man, having been subjected to vanity and a crooked condition by God due to Adam's sin, cannot provide the price needed to redeem even one of his brothers, thus the sacrifice of any sinful human being, no matter how young or how innocent that human being made appear to be to man, would be an unacceptable to Jehovah.
As bleak as the words of Solomon and Psalmist may appear, neither said that there was no way for man to be redeemed. Both, however, in effect, stated that sinful man cannot redeem himself.
Paul agreed with Solomon, when he wrote:
Romans 8:20-22 - The creation was subjected to futility, not willingly, but because of Him who subjected it, in hope that the creation itself also will be set free from its slavery to corruption into the freedom of the glory of the children of God. For we know that the whole creation groans and suffers the pains of childbirth together until now.
The "creation" Paul speaks of is not in reference to angels. Neither the Hebrew scriptures nor the Christian New Testament ever speak of the angels as being under a bondage of corruption, or having been made crooked, etc. Thus the 'whole creation' that Paul speaks of is the old human creation (as contrasted with the new creation, the sons of God that Paul spoke of in Romans 8:16; 2 Corinthians 5:17; mankind, being under subjection as sun of crookedness, cannot free himself from that crooked condition.
The Psalmist declared that man's redemption is costly; it is some far beyond the ahility of sinful man to provide. However, Genesis 3:15 indicates that it was God intention to reverse the condemnation that had come upon man due to Adam's sin. According what is stated, however, taht seed was to bruised in the heel, while serpent was to bruised in the head. This indicates the costly price needed to redeem mankind. The redemption price would be a man, but it could not be a man of Adamic stock, for such a man cannot even justify himself. That man would have be born separate from the condemnation in Adam, so as not be crooked, sinful. Since man, under the present sun of crookedness, cannot produce a new creation, a creation that is not under the present sun that upon man through Adam. Such a man would not be under the subjection to the crooked condition of mankind.
Isaiah foretold of such a man, speaking as the children of Israel after that man had come:
Isaiah 53:2-10 - He has no form nor magnificence that we should see Him; nor form that we should desire Him. 3 He is despised and abandoned of men, a Man of pains, and acquainted with sickness. And as it were hiding our faces from Him, He being despised, and we did not value Him.
4 Surely He has borne our sicknesses, and He carried our pain; yet we esteemed Him plagued, smitten by God, and afflicted. 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 wounds we ourselves are healed. 6 All we like sheep have gone astray; we have each one turned to his own way; and Jehovah made meet in Him the iniquity of all of us. 7 He was oppressed, and He was afflicted, but He did not open His mouth. He was led as a lamb to the slaughter; and as a ewe before her shearers is dumb, so He opened not His mouth. 8 He was taken from prison and from justice; and who shall consider His generation? For He was cut off out of the land of the living; from the transgression of My people, the stroke was to Him. 9 And He appointed Him His grave with the wicked, but He was with a rich man in His death; though He had done no violence, and deceit was not in His mouth. 10 But Jehovah pleased to crush Him, to make Him sick, so that If He should put His soul as a guilt offering. -- Green's Literal.
He further says that this one "shall justify [be a means of justification, being made straight] for many, and He shall bear their iniquities." (Isaiah 53:11)
And, "He poured out His soul to death; and He was counted with those transgressing; and He bore the sin of many, and made intercession for those transgressing." -- Isaiah 53:12.
Here we have the description of the one who was be sacrificed -- cut off out of the land of the living -- for our sins. It is indeed a costly price for one who sinless to pay.
The NT tells us that it was God who prepared Jesus' body. (Hebrews 10:5) Thus, he was not born into this world under the condemantion that is in Adam that Paul wrote about. He had the costly price acceptable to God needed to redeem mankind, and he did so. -- Romans 5:12-19; 1 Corinthians 15:21,22; 1 Timothy 2:5,6.