Mankind is alienated from God. Thats why those who are disciples of Christhave been to the top of the mountainmust come back down with a purpose. If we have been reconciled with Godmade right in our relationship with Himit makes sense that God would use us to help others be reconciled with Him. He will also help us find reconciliation in our own relationships and use us to help others find reconciliation in theirs. The seventh beatitude speaks to the mission of those who are part of Gods solution.
Scripture References: Matthew 5:9