“A faithful friend is a strong defense: and he that has found him, has found a treasure. Sirach 6:14
Jesus had a lot to say about friends. He even called some of his contemporaries friends. He called Lazarus his friend.
…he said to them, “Our friend (φιλοσ) Lazarus has fallen asleep, but I go to awaken him. John 11:11
It is from Jesus we get the great quote about friendship, though to be fair it is intimately linked to agape.
Greater love (αγαπη) has no one than this, that someone lays down his life for his friends (φιλοσ). John 15:12-13
Right after that, Jesus directly calls his disciples his friends.
No longer do I call you servants, for the servant does not know what his master is doing; but I have called you friends (φιλοσ), for all that I have heard from my Father I have made known to you. John 15:15
However, while a true friend will lay down his life for you, some friends will betray you, your Christianity coming between you and their friendship.
You will be delivered up even by parents and brothers and relatives and friends (φιλοσ), and some of you they will put to death. Luke 21:16
The next illustration points out the problems with translations. When Judas betrayed Jesus in the garden, Jesus still, according to most translations, calls him friend.
And he [Judas] came up to Jesus at once and said, “Greetings, Rabbi!” And he kissed him. Jesus said to him, “Friend, do what you came to do.” Matthew 26:49-50a
The actual word used here is not philos (φιλοσ) but hetairos (εταίροσ), which means a comrade, a companion rather than a friend. As Vines points out, it is a term of comradeship rather than endearment, which philos conveys. With that caveat to translations, there is one passage in Luke that is a bit difficult.
And I tell you, make friends (φιλοσ) for yourselves by means of unrighteous wealth, so that when it fails they may receive you into the eternal dwellings. Luke 16:9
At first glance, it almost appears Jesus is talking about attempting to bribe your way into heaven, buying heavenly friends. But I think the best commentary on this passage comes from Paul in his first letter to Timothy.
As for the rich in this present age, charge them not to be haughty, nor to set their hopes on the uncertainty of riches, but on God, who richly provides us with everything to enjoy. They are to do good, to be rich in good works, to be generous and ready to share, thus storing up treasure for themselves as a good foundation for the future, so that they may take hold of that which is truly life. 1 Timothy 6:17-19
You cannot buy friends (at least not real ones) or bribe your way into heaven. Instead, by being charitable with your money, having a giving heart and helping those in need, what used to be called almsgiving, you produce good works for the Kingdom of God. More than that, you can use mammon to support the work of God as he so directs. Since your focus is on God and giving (not what you get out of it), you turn what would otherwise be fools gold, or as one preacher noted, heavenly paving bricks, into real, eternal treasure.
We all long to hear Jesus call us friend and it is my prayer, dear reader, that your longing will be fulfilled; that when you approach the throne of grace, those you helped will be there to joyfully receive you. May that grace be yours.