This verse from 2 Maccabees 15:26 ("but Judas and his company joined battle with the enemy with invocation and prayers") means that Judas Maccabeus and his soldiers went into battle against their enemies while praying to God for help and support.

Here's a breakdown:

Judas and his company: Refers to Judas Maccabeus, the leader of the Jewish rebellion against the Seleucid Empire, and his army of Jewish fighters.
joined battle with the enemy: They engaged in combat with their adversaries, the Seleucid forces who were trying to suppress Jewish religious practices and culture.
with invocation and prayers: This is the key part. It emphasizes that before and as they went into battle, they were calling upon God (invoking) and offering prayers. This indicates:

Reliance on God: They believed that victory was not solely dependent on their own strength and skill, but on divine assistance.
Spiritual Preparation: Prayer was a way of preparing themselves mentally and spiritually for the challenges of war.
Moral Justification: By praying, they were also seeking assurance that their cause was righteous and deserving of God's blessing. They viewed the Seleucid oppression as an attack on their faith and way of life.
Community: The prayers were likely collective, reinforcing a sense of unity and shared purpose among the soldiers.

Context is important:

The books of Maccabees are historical accounts written from a religious perspective. They highlight the importance of faith in the face of adversity and portray the Maccabean revolt as a holy war. This verse underscores the authors' belief that God intervened in the events and helped the Jewish people to overcome their enemies.

In essence, this verse portrays Judas and his forces as devout warriors who relied on prayer as a vital part of their battle strategy and moral foundation.