As for present-day German: No.
"Soll + infinitive" has two basic meanings:
- a (strong) wish or an order
- hearsay: "Er soll sehr intelligent sein." = "He's said to be very intelligent."
As for Luther:
The Vulgata has "et gaudebit cor vestrum, et gaudium vestrum nemo tollet a vobis", which is the future tense, not the conjunctive, and the Greek (which I don't understand) has χαρήσεται, which Google says is future tense.
So Luther obviously used "sollen" for the future tense here.
Now, on to Heine:
Und wenn du mich lieb hast, Kindchen,
Schenk' ich dir die Blumen all',
Und vor deinem Fenster soll klingen
Das Lied der Nachtigall.
The second line is written in present tense, which is often used in place of the future tense. The speaker says what he will do. In lines three and four, he wishes that the nightingale will sing a song, but he is in no position to accurately predict what will actually happen.
So, in short, "sollen" probably had a future meaning some time in the distant past. It doesn't have such a meaning now.