Richard,

These situations require great care because your brother may be coming to a greater faith in Christ through the other church community so anything you say to him may seem as an affront to the faith.

Therefore you should proceed by affirming what is good and true but then direct him toward the fullness of truth that only the Catholic Church possesses.

You can't argue about the wrongness of his actions and expect to win him over. You must encourage him to look at the big issues on:

• Authority
• Scripture,
• Tradition, and
• the Sacraments.

He likely was baptized with them because he thinks it is a profession of faith and act of obedience, but misses their true covenant meaning and efficacy.

You cannot help him until you become very knowledgeable about your faith as a Catholic and can explain it with Scripture and Tradition.

Use sites like this, in addition to reading and prayer to equip yourself appropriately.

Peace,

Bob Kirby