What's the source of "I can only give what I have"? Right now, I'm reading When Heaven Invades Earth by Bill Johnson. I just came across this sentence: "If I am filled with anxiety in any given situation, it becomes hard for me to release peace--because I can only give what I have." (Emphasis mine.)

The phrase by itself is a good and noteworthy one, but the reason I'm posting this question is that I've heard this phrase used before, spoken by Mike Cavanaugh. Both Bill Johnson and Mike Cavanaugh have done many great things by following the Lord, both are senior pastors, and both have used this phrase. This suggests to me that there's an earlier source that both have read and drawn from. Hence, I ask: does this earlier source exist, and if so, what is it?



I kept reading and I came across "As glorious as the gift of tongues is, it is an entrance point to a lifestyle of power.", which is another thing Mike Cavanaugh said. The answer to this question may very well be a negative in that Mike may have drawn from this book, not an earlier source. If this is the case, an answer should show this.
I don't know the original source, but if it is based on Scripture (which certainly seems plausible), here are some passages which may relate:


  When [the beggar] saw Peter and John about to go into the temple, he began asking to receive alms. ...But Peter said, “I do not possess silver and gold, but what I do have I give to you: In the name of Jesus Christ the Nazarene—walk!” - Acts 3:3-6


Peter and John had a command from Jesus to give to anyone who asked of them - but they couldn't give the beggar alms because they didn't have any money.  (NOTE: Not having it and thinking you can't afford it are two different things.)


  And God has appointed in the church, first apostles, second prophets, third teachers, then miracles, ...various kinds of tongues. All are not apostles, are they? All are not prophets, are they? All are not teachers, are they? All are not workers of miracles, are they? ...All do not speak with tongues, do they? - 1 Corinthians 12:28-30


We are only capable of moving in the "Spiritual Gifts" which we have been given.


  You brood of vipers, how can you, being evil, speak what is good? For the mouth speaks out of that which fills the heart. The good man brings out of his good treasure what is good; and the evil man brings out of his evil treasure what is evil. - Matthew 12:34-35


We are only capable of verbalizing that which we already have in our heart.


  For the mind set on the flesh is death, but the mind set on the Spirit is life and peace, because the mind set on the flesh is hostile toward God; for it does not subject itself to the law of God, for it is not even able to do so - Romans 8:6-7


The mind set on the Spirit has peace.  The fruit of walking by the Spirit is peace.  The result is making peace through peaceful means.  Alternatively, if you set your mind on the flesh, you will experience death instead of peace, and the result will be the opposite of peace.  In other words, if you have peace you can impart peace, but if you don't have peace, you can't impart peace.