Propitiation cannot be provisional? Christ became the propitiation for the whole world, but the whole world is not saved. Therefore it is provisional, it provides the means of salvation for everyone who believes.
The assertion, propitiation cannot be provisional, is yet another attempt to rewrite the meaning of words to pour Calvinism into scripture. Note to put too fine a point on it but a propitiation is something that propitiates. Thus, by its very nature, it is provisional.
Scripture does not read, Christ propitiated to indicate a one time action, it says He became the propitiation for the whole world, 1 John 2:2.
Calvinism, as represented by the TULI, cannot be defended with scripture, unless you revise the scripture by changing the word meanings or grammar or both.
How do we receive the benefits of His propitiation? By being chosen individuallly before creation? Nope, we are chosen during our lifetime, placed in Christ spiritually, and God's wrath is taken away - the penality for our sins past, present and future - by the circumcision of Christ. Anyone God puts in Christ receives the propitiation, anyone not in Christ gets no benefit from Christ's sacrifice on the cross, they face the wrath of God who is angry with sinners every day.