The interpretation timeline
Sirach 42:19 Douay-Rheims

For the Lord knoweth all knowledge, and hath beheld the signs of the world, he declareth the things that are past, and the things that are to come, and revealeth the traces of hidden things.

2 witnesses

Post-Reformation

c. 1650 – 1900
1849
A.D.
1774–1849
“Signs. Literally, “sign,” the order of the stars, &c. (Haydock) — Yet God does not study these things, to discover what will happen. He is the author of nature. (Calmet) — From his works we are to form some idea of his greatness, Job xxxviii., &c. (Worthington)”

Undated

date unknown
date
unknown
Glossa Ordinaria Medieval
“For the Lord hath known, etc. Because all the ages of the world are present to him, with whom nothing is past, nothing to come; he alone reveals mysteries, who knows the hearts of each, who beholds all thoughts and words.”
Modern · 1953 →

The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.