While on the Millennium Falcon training Luke, Obi-Wan is shaken and is forced to sit down.
When Luke asks if he is alright, Obi-Wan replies, "I felt a great disturbance in the Force, as if millions of voices suddenly cried out in terror and were suddenly silenced. I fear something terrible has happened."
As a Jedi, Obi-Wan was trained to be in tune with the Force. When Alderaan was destroyed, all that death created a great disturbance in the Force, a sense of grief.
The Holy Spirit of God can be grieved. We are told in Ephesians 4:30, "do not grieve the Holy Spirit of God, by whom you were sealed for the day of redemption."
If the Holy Spirit could not be grieved, we would not need to be told, "do not grieve the Holy Spirit."
How can we grieve the Holy Spirit?
In Ephesians 4:31-32, we read, "let all bitterness and wrath and anger and clamor and slander be put away from you, along with all malice. Be kind to one another, tenderhearted, forgiving one another, as God in Christ forgave you."
Jesus told His disciples in John 15:13, "Greater love has no one than this, that someone lay down his life for his friends."
We, as Christ-followers, need to love one another. When we love, we cannot be bitter or angry with one another.
What is love?
We are told in 1 Corinthians 13:4-8a, "Love is patient and kind; love does not envy or boast; it is not arrogant or rude. It does not insist on its own way; it is not irritable or resentful; it does not rejoice at wrongdoing, but rejoices with the truth. Love bears all things, believes all things, hopes all things, endures all things. Love never ends."
If we, as believers, live a life characterized by love, we will not grieve the Holy Spirit.