It is common in theology as in many other fields of knowledge to define specialized terms when teaching or explaining. Pope Francis has defined proselytize, as he uses the term, in the negative; then he uses evangelize in the positive. The distinction is between a holy loving grace-filled spreading of the Gospel — by living the teachings and example of Christ — versus arguing and pressuring others to join your own personal version of the gospel. The Pharisees proselytized, while John the Baptist evangelized.

[Matthew]
{23:15} Woe to you, scribes and Pharisees, you hypocrites! For you travel around by sea and by land, in order to make one convert [Latin: unum proselytum]. And when he has been converted, you make him twice the son of Hell that you are yourselves.

Don’t proselytize, like the Pharisees. Evangelize like Jesus, John, and the Apostles. Those who proselytize wish to make others just like them. Instead of seeking converts for Jesus, by evangelization, so that the converts will be led by grace and providence by the will of God, those who proselytize which to make carbon-copies of themselves.

This “be like one of us” attitude is not a spreading of the true Gospel, the truth of which is from Christ through the Church. Instead it is either the individual version of the gospel, distorted by an individual pride-filled religious leader, or, so often, it is a version of the gospel distorted by a subset of Catholics or other Christians.

This is seen in certain (not all) traditionalist Catholics, the hyper-traditionalists, who wish to make converts, not to Christ or the Church, but to their own schismatic and heretical version of the gospel. They convert others to hate Pope Francis, to distrust the body of Bishops and the two recent Councils (Vatican I and II). They do not want their converts to be led by the Holy Spirit or the Church, as that would conflict with their own highly-politicized version of religion and their opposition to Popes, Bishops, and Councils. And these are the same persons who attack Pope Francis for opposing proselytizing, misrepresenting the Pope as if he were opposed to evangelization.

Here is Pope Francis’ recent General Audience on this topic.

Ronald L Conte Jr