…..for the occasion of the upcoming “Year of Consecrated Life”. Recall that, there are certain conditions that must be met in order to obtain a plenary indulgence. Even if you are not disposed to receiving a plenary indulgence — that is, complete remission of all temporal punishment due to sin — because, for example, you retain some attachment — however small, to sin — since the attachment can be to sins that are venial only — the indulgence you receive may be partial, which is still a spiritual work of mercy, and doubtless is appreciated by a soul in Purgatory.
I don’t think we’re supposed to spend much time trying to figure out whether indulgences are truly plenary or partial. Over the years the Church has developed in its own understanding of the authority given to “bind and loose”. If God (and Heaven, and by extension Purgatory) stands outside of time and space, it becomes nebulous to quantify “time” in Purgatory. And yet, we believe (and it seems, know) that some prayers, some work, some actions, are more efficacious than others.
God knows our hearts and He knows the intention we bring. He accepts all earnest prayers, and we know that He is just and merciful. We can trust that when we are called to pray for souls who need prayers, our prayers have effect. So just do it.