Catholicism is not a sect, and while it is rigid in Christ's teachings, the teaching on the Lutherans is: Their communions can be genuine spiritual encounters with Christ.
We share with them in the basic expression of Christian unity -- prayer to the One Lord, God and Savior Jesus Christ
“well, they are considered true brethren. And we can share the basic expression which is praying together.”
You can pray with a Muslim, so you’re just making me chuckle at this point. If you considered them true brethren, then your church would have no problem with you sharing the “family meal” with them.
“Catholicism is not a sect, and while it is rigid in Christ’s teachings, the teaching on the Lutherans is: Their communions can be genuine spiritual encounters with Christ.”
Call it what you want, but you are misleadingly leaving out a very relevant portion of your church’s teachings on this matter. You acknowledge that there could be something genuine there, but you can’t participate in it together:
“Ecclesial communities derived from the Reformation and separated from the Catholic Church, “have not preserved the proper reality of the Eucharistic mystery in its fullness, especially because of the absence of the sacrament of Holy Orders.” It is for this reason that Eucharistic intercommunion with these communities is not possible for the Catholic Church. However these ecclesial communities, “when they commemorate the Lord’s death and resurrection in the Holy Supper ... profess that it signifies life in communion with Christ and await his coming in glory.” (Catechism of the Catholic Church, number 1400)
“Because Catholics believe that the celebration of the Eucharist is a sign of the reality of the oneness of faith, life, and worship, members of those churches with whom we are not yet fully united are ordinarily not admitted to Holy Communion. Eucharistic sharing in exceptional circumstances by other Christians requires permission according to the directives of the diocesan bishop and the provisions of canon law. (canon 844 § 4)”
http://old.usccb.org/liturgy/q&a/mass/communion.shtml