I'm curious how you can observe two laws. For example, now that Jesus is high priest the law has changed because he can't be high priest under the Mosaical law.
Heb. 7:11 Therefore, if perfection were through the Levitical priesthood (for under it the people received the law), what further need was there that another priest should rise according to the order of Melchizedek, and not be called according to the order of Aaron? 12 For the priesthood being changed, of necessity there is also a change of the law. 13 For He of whom these things are spoken belongs to another tribe, from which no man has officiated at the altar.
14 For it is evident that our Lord arose from Judah, of which tribe Moses spoke nothing concerning priesthood.
Also, look at what Paul says in Romans 7. By observing both laws, one is in effect committing spiritual adultery.
Rom. 7:1 Or do you not know, brethren (for I speak to those who know the law), that the law has dominion over a man as long as he lives? 2 For the woman who has a husband is bound by the law to her husband as long as he lives. But if the husband dies, she is released from the law of her husband. 3 So then if, while her husband lives, she marries another man, she will be called an adulteress; but if her husband dies, she is free from that law, so that she is no adulteress, though she has married another man. 4 Therefore, my brethren, you also have become dead to the law through the body of Christ, that you may be married to another—to Him who was raised from the dead, that we should bear fruit to God. 5 For when we were in the flesh, the sinful passions which were aroused by the law were at work in our members to bear fruit to death. 6 But now we have been delivered from the law, having died to what we were held by, so that we should serve in the newness of the Spirit and not in the oldness of the letter.
What is your stance on circumcision, necessary or not?