With regard to Justification and Salvation

I had an interesting discussion with both Catholic, Orthodox, and my Pastor about Election and what it means to be justified. I'm not certain of all the ramifications and want to bring it up here to get a view of what people thought. My Pastor and I have always held to legal form of justification. Ie... we are "declared" righteous and we are "in" Christ legally which Jesus secured for us on the cross and by his resurrection. The Orthodox and the Catholic both claim that we are not only "declared" so in a legal aspect but "made" such (since there was discussion on what the actual greek word used in this context was). That Jesus not only legally allowed for our attonement but we are "inserted" into the Father's relationship with the Son. Not in the communion as Part of the trinity but as Jesus was incarnated and took on humanity (without the sin) we take on Christ so that we are in truth God's children. They go one step further and state that with baptism we are marked as God's (we not only look like Jesus to God but smell like him to use a metphore which I understand since I have a 1 1/2 year old that I smell his head and know he's mine). Which my Pastor and I debate. Yet my pastor seemed to indicate that this was a theologically dangerous ground to tread for the Orthodox and Catholic and I'm wondering why. In area's I don't understand I usually just listen to see what people are saying. Since, I'm confused on this matter I wonder what the problems people here see with it. The baptism aspect is easy. I know what everyone will say about that. I'm curuios about the part of being inserted into Christ.