The Church Fathers, almost from the beginning of Church History, found further Scriptural evidence by comparing the figure of Eve to the figure of Mary. St. Justin Martyr said that Mary was a kind of New Eve, “in order that the disobedience which proceeded from the serpent might receive its destruction in the same manner in which it derived its origin.” (Dialogue with Trypho, 100) Tertullian argued in the same manner, saying, “As Eve had believed the serpent, so Mary believed the angel. The delinquency which the one occasioned by believing, the other by believing effaced.” (On the Flesh of Christ, 17) St. Irenaeus declared that Mary became “the cause of salvation, both to herself and the whole human race,” because “what the virgin Eve had bound fast through unbelief, this did the virgin Mary set free through faith.” (Against Heresies, Book III, cap. 22, 4) St. Jerome coined the phrase, “Death came through Eve, but life has come through Mary,” (Letter XXII, To Eustochium, 21). In addition “Blessed shall be the fruit of thy womb” is a reward for obedience to God by keeping the commandments.[Neutrality disputed — See talk page][3]
The Catholic Encyclopedia of 1914, however, states that these scriptures merely serve as corroborative evidence assuming that the dogma is already well established, and that there is insufficient evidence to prove the dogma to someone basing their beliefs solely on biblical interpretation:
No direct or categorical and stringent proof of the dogma can be brought forward from Scripture. …The salutation of the angel Gabriel — chaire kecharitomene, Hail, full of grace (Luke 1:28) indicates a unique abundance of grace… but the term kecharitomene (full of grace) serves only as an illustration, not as a proof of the dogma. ― Catholic Encyclopedia — Immaculate Conception

roof from Scripture
Scripture verses sometimes used to show her Immaculate Conception (other than Luke 1:28) are
“And you shall make the ark of testimony of incorruptible wood And you shall gild it with pure gold, you shall gild it within and without; and you shall make for it golden wreaths twisted round about.” (Exodus 25:10-11 Brenton LXX)
“So I made an ark of boards of incorruptible wood, and I hewed tables of stone like the first, and I went up to the mountain, and the two tables were in my hand.” (Deuteronomy 10:3 Brenton LXX)
Other translations use the words “setim,” “acacia,” “indestructible,” and “hard” to describe the wood used. In any case, Moses used this wood because it was regarded as very durable and “incorruptible.” Mary is regarded by Catholic and Orthodox Christians as being the Ark of the Covenant in the New Testament and therefore it would seem fitting that the New Ark likewise be made “incorruptible” or “immaculate.” The basis for called the Virgin Mary the Ark of the Covenant is based partly on the parallels of the Ark in Second Samuel 6 with the Nativity narrative of the Gospel of Luke. The Early Church Fathers have called Christ, the Church, and the Virgin Mary each at one point as being symbolized by the Ark. [4]
Mary is also shown as being totally faithful towards Christ, especially during his Passion, when he was abandoned by His followers, even the apostles (apart from the young John). Mary’s complete faithfulness could be the fruit of being sinless, as she could not then reject Christ in the darkest hour. In support to this doctrine, it also does not appear fit that Christ, God-incarnate, should be born in sinful vessel.
The Immaculate Conception also compares to the original righteousness of Adam and Eve. Also, as she is coneived without sin, Catholics use it in the argument that life starts at conception.