Muslims believe they worship the God of Abraham, what I believe is that they worship in vain since they deny Christ. You and I are not as far apart as you want to believe, I just don’t see any point in saying that they don’t believe in what they claim to believe in. I think and the catechism states that the gift of a monotheistic belief, even one as defective as the one they have, contains and element of truth, and all truth is form God, was given to the Muslim people for a reason. What that reason is and what God’s plan is for the conversion of the Muslims is beyond me, all I can say is Thy will be done!
Calvinism, like Mohammedanism, is a perversion of Truth, one more deadly than the other, but both poison.
Agreed that all truth is from God, yet something that merely contains an element of truth is no longer truth.
Consider a lie.
A lie is in essence a twisted truth. It has enough truth in it to confuse and appeal, yet digresses at some important point.
We can affirm that which is true, but it is also important (in God’s time and in God’s ways) to teach, correct and rebuke where the truth has been distorted.
As to Benedict’s statement on Protestants, I would suggest we all judge by the standards of scripture. Look for evidence of the workings of the Holy Spirit, which is the seal of Christ upon man (Ephesians 1:14). Look for evidence of the fruit of the Spirit (love, joy, peace, goodness, faithfulness, gentleness and self-control. Gal 5:22), a love for their neighbour, a love of God and his Word, and obedience to that Word (James 1:22-25, Matthew 28:20).
God’s ‘church’ is not a building or a denomination, but the body of Christ (Col 1:24) which is made up of all those who are baptized in His Spirit (1Cor 12:13). It is not headship to a human Pope we should be looking to, but headship and clear ‘succession’ from Christ Jesus.
Within these standards, I see little to no reference to Apostolic Succession or human (or alter Christus, acting in persona Christi) delivery of the Eucharist as standards for determining a ‘church’.