‘ But the Spirit of Yahweh clothed Himself with Gideon, and he blew a trumpet (of ram's horn) and Abiezer was gathered together after him.'
Yahweh now prepared to go into battle on behalf of Israel, in Gideon's body through His Spirit. He ‘clothed Himself' with Gideon. This did however require Gideon's response and obedience. God does not force Himself on people. The result was that his own sub-tribe gathered in his support.
Word of his experiences and all that had happened to him had spread around and there was renewed hope in Yahweh at this hopeless time. Since being renamed Jerubbaal he had seemed only to prosper and Baal had been able to do nothing against him. This demonstrated clearly that Yahweh was with him. All the memories of what Yahweh had done in the past had come flooding back. And they were very conscious of the raiders again poised to strip them of everything.
“And he blew a ram” s horn, and Abiezer was gathered together after him.' The call went out for them to gather to deal with the enemy in the name of Yahweh, and the first response came from his own sub-tribe. The Abiezrites were one of the sub-tribes of the tribe of Manasseh, to which Gideon and his father's house belonged.
We are not specifically told that the people of Ophrah were reconciled to him, but they may well have been made to rethink by the course of events. When they cooled down they may well have felt that one who could stand against Baal, ‘the rider of the clouds', in the name of Yahweh, could deal with this dreadful enemy who were ruining their lives. Baal was fine for producing crops but he seemed helpless against Gideon and against the Midianites.