Hmmm. Thanks for this question. First, it prompted me to read the relevant section in the Catechism of the Catholic Church (paragraphs 1776-1802). In brief, the Catechism says this-

1. Man must obey his conscience.
2. Man must recognize that his conscience can be erroneous and seek to inform it.
3. Conscience can remain in ignorance, and such ignorance can often be imputed to personal responsibility. So man cannot say that "well, my conscience compelled me to do it, so I cannot be blamed". (In the case that the priest refers to, this 3rd clause most definitely applies. Those people whose consciences tell them to vote in opposition to Catholic teaching must ensure that they inform their consciences).

We can safely assume that Pope Benedict XVI, being a practicing Catholic, holds all of the above three.

Now, coming to the text you cited, what struck me was the first two words -

"For Newman..."

The rest that follows is therefore Newman's opinion, not Joseph Ratzinger's opinion!! Joseph Ratzinger was simply explaining the position held by Newman, who was still an Anglican at that time and was opposed to the claims of the Catholic Church. This is pointed out even in the footnotes of the Catechism of the Catholic Church. The footnote for CCC 1778 says -

John Henry Cardinal Newman, "Letter to the Duke of Norfolk," V, in Certain Difficulties felt by Anglicans in Catholic Teaching II (London: Longmans Green, 1885), 248.

If we read the letter cited in the above footnote, we find that Newman (who later converted to Catholicism) expressed his opposition to Catholic teaching in it.

Therefore, you are right that the citation sounds odd. It sounds odd if you think that the first part of the citation is Joseph Ratzinger's opinion. However, if you recognize that Joseph Ratzinger was first simply mentioning Newman's opinion and then mentioned his own opinion, Ratzinger's views become clear.

Although my reply to this question is finished, I do want to say that it's unfortunate to see a Catholic priest quoting Joseph Ratzinger out of context to make a point.

Hmmm. Thanks for this question. First, it prompted me to read the relevant section in the Catechism of the Catholic Church (paragraphs 1776-1802). In brief, the Catechism says this-

1. Man must obey his conscience.
2. Man must recognize that his conscience can be erroneous and seek to inform it.
3. Conscience can remain in ignorance, and such ignorance can often be imputed to personal responsibility. So man cannot say that "well, my conscience compelled me to do it, so I cannot be blamed". (In the case that the priest refers to, this 3rd clause most definitely applies. Those people whose consciences tell them to vote in opposition to Catholic teaching must ensure that they inform their consciences).

We can safely assume that Pope Benedict XVI, being a practicing Catholic, holds all of the above three.

Now, coming to the text you cited, what struck me was the first two words -

"For Newman..."

This means that Joseph Ratzinger is referring to Newman's views on the subject. Now, Newman is quoted in the Catechism, paragraph 1778. The footnote for CCC 1778 says -

John Henry Cardinal Newman, "Letter to the Duke of Norfolk," V, in Certain Difficulties felt by Anglicans in Catholic Teaching II (London: Longmans Green, 1885), 248.

If we read the letter cited in the above footnote, we find that Newman explains his position on conscience. According to Newman, conscience must always be obeyed. He also says that conscience and papal infallibility can never be in conflict. According to Newman, conscience and ecclesiastical authority can be in conflict in matters that do not pertain to infallibility. But Newman also agrees that it is possible to have an erroneous conscience. I suppose that Ratzinger holds the same, namely that conscience should be obeyed over and above the pope in matters where the pope is not infallible, whereas genuine ecclesiastical obedience is expected in matters where he is.