well the God im worshiping is the Jewish God, so i will certainly apply those jewish laws to my christian faith
The God every one worships is the same God. That is if we believe there is only one god.
Perhaps your comment indicates that you dont recognize Yahweh as God, and therefore i can understand why you would consider jewish law irrelevant.
As my answer above... the name we ascribe to God is irrelevant, and only indicate our religions nomenclature.
But you should probably take into consideration that Jesus himself was a worshiper of Yahweh/Jehovah and the laws he lived by were the jewish laws.... his own morals were based on those laws, so by learning those laws, we can understand Jesus even more fully which can only be considered a good thing.
Jesus was a Jew and like all Jews, avoided using names that they ascribed to God.
His morals were based on Judaism. However in his teachings he change the emphasis from the negative Idea of a law based list of sins, to an positive Idea based one, which put the emphasis on sins of omission. This is indicated most clearly in the Beatitudes. Which give a very positive expression of what he admired and wanted us to follow. It changed the basis from one of "Fear" to one of "Love"
and you dont think sex before marriage is harmful in some ways? Millions of unmarried young mothers is not harmful to their children or themselves? Teenagers who have to leave school to look after a baby is not harmful to her future prospects for finding work?
Sex before marriage Is no more and no less sinful than sex after marriage.
Many people chose not to marry, and can live their lives and raise their children as equally well as married couples. Most marriages these days have no religious content at all. In the majority of Protestant countries only civil marriage is legal.
It is not sinful to be a single mother, or for a Gay couple to conceive and bring up children.
Contrary wise it is sinful to rape your wife or partner or otherwise abuse them.
Teenagers who conceive are perhaps ill advised, and should have use contraception. The potentially hard life that may follow is not sinful. nor is the sex or the getting pregnant.