22 When Christians pray together, the goal of unity seems closer. The long history of Christians marked by many divisions seems to converge once more because it tends towards that Source of its unity which is Jesus Christ. He "is the same yesterday, today and forever!" ( Heb 13:8). In the fellowship of prayer Christ is truly present; he prays "in us", "with us" and "for us". It is he who leads our prayer in the Spirit-Consoler whom he promised and then bestowed on his Church in the Upper Room in Jerusalem, when he established her in her original unity. Along the ecumenical path to unity, pride of place certainly belongs to common prayer , the prayerful union of those who gather together around Christ himself. If Christians, despite their divisions, can grow ever more united in common prayer around Christ, they will grow in the awareness of how little divides them in comparison to what unites them. If they meet more often and more regularly before Christ in prayer, they will be able to gain the courage to face all the painful human reality of their divisions, and they will find themselves together once more in that community of the Church which Christ constantly builds up in the Holy Spirit, in spite of all weaknesses and human limitations.
Source: Ut Unum Sint (Vatican.va)