The following are notes from : Traditional Values, Governmental Values, and Religious Conflict in Contemporary India” by Robert D. Baird. It is from the Brigham Young University Law Review and you can access it by clicking on the link.
~ Baird points out that in 1967 and 1968, Orissa and Madhya Pradesh passed anti-conversion laws. These laws were challenged and the cases went to the Supreme Court. The Supreme Court ruled in favor of the anti-conversion laws and did so by making a distinction between the right to propagate and the right to convert. Propagation was legal, whereas conversion was deemed not to be a fundamental right.
With reference to Article 25(1), Chief Justice Ray writing for the Court would say the following:
“What the Article grants is not the right to convert another person to one’s own religion, but to transmit or spread one’s religion by an exposition of its tenets. It has to be remembered that Article 25(1) guarantees “freedom of conscious to every citizen, and not merely to the followers of one particular religion and that, in turn, postulates that there is no fundamental right to convert another person to one’s own religion because if a person purposely undertakes the conversion of another person to his religion, as distinguished from his effort to transmit or spread the tenets of his religion, that would impinge on the “freedom of conscience” guaranteed to all the citizens of the country alike.”
~ Baird does not comment all that much on this unfortunately because it does not make sense. In the little that he says, he states:
“Whatever else might be said about these bills and their treatment by the Supreme Court, they at least present a constriction upon religion as constitutionally understood.”
Baird then goes on to point out a court case where an 81 year old priest, Fr. Brigit and 50 year old nun, Sister Ekka were tried, sentenced and imprisoned for violating the MP Acts. They apparently failed to register the conversions. (According to the MP Acts, you have to hold an official conversion ceremony, invite certain public officials and register the conversions by providing personal information of the converts. Failure to do so will result in imprisonment.)
Ok. Going back to Justice Ray’s comments. He basically states the following:
 Article 25(1) gives the right to propagate but not the right to convert.
 Article 25 also provides freedom of conscience to everyone without exception.
 On account of freedom of conscience being given to everyone, you cannot convert anyone (i.e. conversion is wrong).
[3.1] For a person X to convert a person Y in a manner distinct from propagation would be for X to violate Y’s freedom of conscience.
This does not make sense.
~ What  seems to be saying is that conversion and freedom of conscience are mutually exclusive. You cannot convert without violating one’s freedom of conscience. Why? Why think that this is the case? I am not a lawyer but this seems to me to be wrong.
~ Perhaps that is why the Chief Justice also said “…if a person purposely undertakes the conversion of another person to his religion, as distinguished from his effort to transmit or spread the tenets of his religion…”
~ I find this to be problematic as well. Does the Chief Justice mean that X can undertake the conversion of Y in a manner that may not be distinguished from propagation? If so then there is some sense in which conversion and propagation are the same activities! So why legalize one and make illegal the other???
Chief Justice Ray’s reasoning seems to be awry.