Is man born in sin? Tehilim 51:7

Tehilim(51:7):. Behold, I was shaped in iniquity, and in sin my mother conceived me.

Rashi (Tehilim 51:7): Behold I was formed in transgression – So how could I not sin. The basis of my being formed was my parents sexual intercouse and through intercourse it is possible to be involved in a number of trangression. And alternative explanation, my principle formation was from male and female – both of them are full of sins. However there are other interprative readings to this verse and they do not conform to the subect matter of the verse.

Vayikra Rabbah (14:5): Another understanding of Vayikra (12:2), If a woman conceives and bears a male child...  Dovid alluded to this understanding in Tehilim (51:7), Behold I was formed in sin and in sin my mother conceived me. Rav Acha explained, Even if a person is the most pious of the pious – it is impossible that he doesn’t have an aspect of sin in him. Dovid said to G‑d, “Master of the Universe, did my father Yishai have the intention to bring me into the world – when he had intercourse with my mother. The fact is that he was only thinking about his own sexual enjoyment.The proof for my assertion is that after they both had satisfied their desires he turned his face in one direction and she turned her face in the opposite direction. And it was only You who caused every single drop of semen to enter.” This assertion is alluded to by Dovid in (Tehilim 27:10), For though my father and my mother deserted me, G‑d did gather me in.

Ibn Ezra (Tehilim 51:7): Behold – because of the lust which are planted in the heart of man  it is equivalent to “being formed in sin.” The reason is that at the moment of birth, the evil inclination (yetzer harah) is planted in the heart...

Redak(Tehilim 51:7): Behold in sin I was formed. The Ibn Ezra says it is because of the lust which is planted in man’s heart that is is equivalent to “being formed in sin.” The reason is that at the moment of birth the evil inclination is planted in the heart. However others say that this an allusion to Eve who did not give birth until after she had sinned. 

Alshich (Tehilim 51:7): Behold in sin I was formed – From the time it decreed that I should be born by means of the sin of Lot’s daughter who had an incestual relation with her father which is disgusting and terrible sin – but that is how I was formed. As it says in Bereishis Rabbah (50:16), “I found Dovid My servant” where was he found? In Sedom.  And in sin my mother conceived me  - that is referring to Ruth who is referred to as mother as it says in Bava Basra (91b)... she was the mother of the Davidic monarchy.  From the time when she got the idea of lying at the feet of Boaz which was the sin of chilul Hashem as we see in Ruth Rabbah (6:1) that Boaz prayed that no one would know that she came to the threshing floor. And You G‑d did not consider it bad since You knew the motivation was good....