en_tn_condensed/act/26/14.md

I heard a voice speaking to me that said

Here "voice" stands for the person speaking. Alternate translation: "I heard someone speaking to me who said" (See: rc://en/ta/man/translate/figs-metonymy)

Saul, Saul, why do you persecute me?

This is a rhetorical question. The speaker is alerting Saul to what Saul is doing to him, and implying that Saul should not do that. Alternate translation: "Saul, Saul, you are persecuting me." or "Saul, Saul, stop persecuting me." (See: rc://en/ta/man/translate/figs-rquestion)

It is hard for you to kick a goad

For Paul to resist Jesus and to persecute believers is spoken of as if he were an ox kicking at the sharp stick that a person uses to prod (or "goad") the animal. It means that Paul is only harming himself. Alternate translation: "You will only harm yourself like an ox kicking a goad" (See: rc://en/ta/man/translate/figs-metaphor)