Answer:

Ephesians 4:32
Be kind to one another, tenderhearted, forgiving one another, as God in Christ forgave you.

Mark 6:34
When he went ashore he saw a great crowd, and he had compassion on them, because they were like sheep without a shepherd. And he began to teach them many things.

Colossians 3:12-13
Put on then, as God's chosen ones, holy and beloved, compassionate hearts, kindness, humility, meekness, and patience, bearing with one another and, if one has a complaint against another, forgiving each other; as the Lord has forgiven you, so you also must forgive.

Galatians 6:2
Bear one another's burdens, and so fulfill the law of Christ.

2 Corinthians 1:3-4
Blessed be the God and Father of our Lord Jesus Christ, the Father of mercies and God of all comfort, who comforts us in all our affliction, so that we may be able to comfort those who are in any affliction, with the comfort with which we ourselves are comforted by God.

Genesis 6:6
And the Lord was sorry that he had made man on the earth, and it grieved him to his heart.

Matthew 14:14
When he went ashore he saw a great crowd, and he had compassion on them and healed their sick.

1 Peter 3:8
Finally, all of you, have unity of mind, sympathy, brotherly love, a tender heart, and a humble mind.

1 John 3:17
But if anyone has the world's goods and sees his brother in need, yet closes his heart against him, how does God's love abide in him?

Matthew 9:36
When he saw the crowds, he had compassion for them, because they were harassed and helpless, like sheep without a shepherd.

Colossians 3:12
Put on then, as God's chosen ones, holy and beloved, compassionate hearts, kindness, humility, meekness, and patience,

Psalm 86:15
But you, O Lord, are a God merciful and gracious, slow to anger and abounding in steadfast love and faithfulness.

2 Peter 3:9
The Lord is not slow to fulfill his promise as some count slowness, but is patient toward you, not wishing that any should perish, but that all should reach repentance.

Isaiah 49:15
Can a woman forget her nursing child, that she should have no compassion on the son of her womb? Even these may forget, yet I will not forget you.

Matthew 7:1-2
Judge not, that you be not judged. For with the judgment you pronounce you will be judged, and with the measure you use it will be measured to you.

Romans 12:15
Rejoice with those who rejoice, weep with those who weep.

Lamentations 3:22-23
The steadfast love of the Lord never ceases; his mercies never come to an end; they are new every morning; great is your faithfulness.

Psalm 103:13
As a father shows compassion to his children, so the Lord shows compassion to those who fear him.

Luke 15:20
And he arose and came to his father. But while he was still a long way off, his father saw him and felt compassion, and ran and embraced him and kissed him.

Isaiah 30:18
Therefore the Lord waits to be gracious to you, and therefore he exalts himself to show mercy to you. For the Lord is a God of justice; blessed are all those who wait for him.

Unless otherwise noted, all Bible verses are from The Holy Bible, English Standard Version® Copyright© 2001 by Crossway Bibles, a publishing ministry of Good News Publishers.

Special thanks to OpenBible.info for the data on the most well-known Bible verses.