What was Delivered in Romans 6:17?

Someone at FBC raised a question about the last phrase of Romans 6:17.

The KJV translates:

ye have obeyed from the heart that form of doctrine which was delivered you.

The NKJV translates:

you obeyed from the heart that form of doctrine to which you were delivered.

So which is it? My Hendrickson KJV 1611 reprint shows a footnote next to verse 17 which says "Gr. whereto ye were delivered." And that is indeed the case no matter what Greek text you examine (Bibleworks GNT=NA27, BYZ=Pierpont Robinson Byzantine Text, and the STE=Estienne's 1550 Greek New Testament). The words "form of doctrine" are the direct object of the verb obeyed, and the phrase "to which you were delivered" indicates the destination doctrine, if you will, where believers have been brought in their obedient faith.

It is true that a form of doctrine was delivered to the saints in Rome; but this text emphasizes a different idea, that the believers were delivered to the form of doctrine that saved them. Leon Morris writes on this,

We would expect [Paul] to say that the teaching had been delivered to the Romans, but instead he says that they had been delivered to the teaching...Christians are in subjection to the teaching God has g iven them. They do not have godliness, but godliness has them.(The Epistle to the Romans in the Pillar New Testament Commentary series, p. 263).