Holy Trinity obliges us to the Blessed Virgin Mary
Believing in the Holy Trinity, the Godhead of three distinct Persons in perfect unity, the Father, Son and Holy Spirit, then are we obliged by that affirmation to understand the Blessed Mary to be singularly preserved exempt from all sin and ever virgin?
As an example we say Christ is one Person in the Holy Trinity and is the union of the nature of God and man. Also, we say that the Son of God was begotten and not made, of one essence with the God; when the incarnation took place, at that very moment of conception, the mystery of the union of God and man took place. Without a sinless Mary, the incarnation took place in a corrupted Ark, Christ is born of sin, which of course is an illogical response.
JoeT