I heard the Messenger of Allah (ﷺ) say: "Whoever shoots an arrow in the cause of Allah, then he has the reward of freeing a slave."

This Hadith is Hasan Sahih. Abu Najih is 'Amr bin 'Abasah As-Sulami, and 'Abdullah bin Al-Azraq is 'Abdullah bin Zaid.
Jami` at-Tirmidhi Book 22, Hadith 21
← Previous Hadith ] There are narrations on this topic from Ka'b bin Murrah, 'Amr bin 'Abasah, and 'Abdullah bin 'Amr. This Hadith is Hasan Sahih.

Jami` at-Tirmidhi Book 22, Hadith 20 Next Hadith → "I heard the Messenger of Allah (ﷺ) saying, 'There are two eyes that shall not be touched by the Fire: An eye that wept from the fear of Allah, and an eye that spent the night standing on guard in the cause of Allah."

There are narrations on this topic from 'Uthman and Abu Raihanah.

The Hadith of Ibn 'Abbas is a Hasan Gharib Hadith, we do not know of it except through the narration of Shu'aib bin Ruzaiq.

Jami` at-Tirmidhi Book 22, Hadith 22