fellowship, be participants with, associate with, be allied with

Definition:

In general, the term "fellowship" refers to friendly interactions between members of a group of people who share similar interests and experiences.

In the Bible, the term "fellowship" usually refers to the unity of believers in Christ.
Christian fellowship is a shared relationship that believers have with one another through their relationship with Christ and the Holy Spirit.
The early Christians expressed their fellowship through listening to the teaching of God's Word and praying together, through the sharing of their belongings, and through eating meals together.
Christians also have fellowship with God through their faith in Jesus and his sacrificial death on the cross which removed the barrier between God and people.

Ways to translate "fellowship" could include "a sharing together" or "relationship" or "companionship" or "Christian community."