John Chrysostom

Then he also enumerates them particularly, amplifying his discourse, and multiplying his praise. How? "Partly" (he says) "whilst ye were made a gazing-stock by reproaches and afflictions"; for reproach is a great thing, and calculated to pervert the soul, and to darken the judgment. For hear what the prophet says: "While they daily say unto me, Where is thy God?" And again, "If the enemy had reproached me, I would have borne it." For since the human race is exceedingly vainglorious, therefore it is easily overcome by this. …

Homily on Hebrews 21 ↗

Theophylact of Ohrid

Pay attention to the praise. Namely, a person with a noble soul has need to endure reproaches, as the prophet testifies: "they said to me every day: where is your God?" (Ps. 42:3) and: "for it is not an enemy who reproaches me — that I could bear" (Ps. 55:12); and: "do not deliver me to the reproach of the foolish" (Ps. 39:8). However, Job was indignant against reproach, although he bore all sufferings manfully, like adamant. …

Commentary on Hebrews ↗

Oecumenius

"you endured a great struggle with sufferings, partly." A strong soul is needed to bear accusations and tribulations, even if they are done privately and secretly; however, since they were done openly and in front of everyone (for this means: you were made a spectacle), a stronger one is necessary. …

The Pseudo-Oecumenian Catena on Hebrews ↗

Thomas Aquinas

538. – Then when he says, and on the one hand by abuse and affliction you were made a gazing stock, he shows what these afflictions were. For a person suffers in two ways: in himself by enduring affliction, and in someone else by taking pity on another's affliction. But they suffered in both ways. In regard to the first way, he says, and on the one hand, i.e., with respect to yourselves, you were made a gazing stock, which is very disagreeable for a wise man. …

Commentary on Hebrews ↗