Cyril of Alexandria

The meaning of this is as follows: They have approached and come together, no longer staying apart, not alienated from each other through sin but as if brought close through spiritually taking possession, are joined into one faith and a common spirit. For once they tasted of the Lord and understood that he is good and began to wonder at the beauty of his truth, they did not only keep the gift for themselves but each one generously came to the aid of his brother and his friend.

Commentary On Isaiah 3:5.41:4-6 ↗

Thomas Aquinas

Second, he sets out mutual strengthening: every one shall help his neighbor: they stick one to another (Job 41:8).

Commentary on Isaiah ↗