Not quite. The short answer is for a Sacrament (as we Lutherans see it), there needs to be three things.
1. A clear case of it in the Bible.
2. The Sacrament is for the remission of sins.
3. There is a visible sign (the water of Baptism, the wine/blood and bread/body of Communion)of that grace.
Which is why Confirmation is considered a rite, but not a sacrament (though the terminology and theology is much like it is for the RCC Confirmation). The Office of the Keys and Confession is sometimes regarded as a Sacrament, but sometimes not as there isn't a visible sign (typically), same with ordination (although that is something that is often hinted at).
When my bride and I got married, we did so in her home church (a RCC church). The priest who did our pre Cana stuff and my pastor at time both said that the marriage was valid either way, but the priest said it would be "irregular" if we got married in my Lutheran Church (the pastor was a close friend). Since it is the right of a woman to be married in her home church were I came from, we got married in her church.
Thanks for the explanation on Lutheran sacramental theology....I’ve been curious about this myself lately.
A question tho..I can see clearly the rationale behind reason #1 (clear case in the Bible) and #3 (visible sign).
But why #2, the “remission of sins” stipulation?
Lesson 15: AN INTRODUCTION TO THE SACRAMENTS
Restored Order of the Sacraments of Initiation? Confirmation and First Eucharist together? (Vanity)
"Virtual" Sacraments Ruled Out
Are Sacraments Narrow? (Imparting Grace through the Sacraments)
Catholic Caucus: Regarding Sinful priests, and Validity of Mass/Sacraments
The Early Church Fathers on The Real Presence - Catholic/Orthodox Caucus
The Early Church Fathers on Confession / Reconciliation - Catholic/Orthodox Caucus
The Early Church Fathers on Baptism - Catholic/Orthodox Caucus