I had not been a Christian very long when I heard a lesson on the inspiration of the scriptures (in direction connection to 2 Timothy 3:16) that used an example from Acts 20:35. The example left such an impression that I have repeated it a few times throughout the last decade. Perhaps you are familiar with the example.
During the lesson the speaker used Paul’s quotation of Jesus (it is more blessed to give than to receive) and then “challenged” someone to show him where Jesus could be quoted in the gospel saying such. Although none doubted the truthfulness of Acts 20:35, an answer could not be provided.
While the general point of the lesson on inspiration is still true (think Jannes and Jambres in 2 Timothy 3:8), I have found where Acts 20:35 can be “quoted” in the gospels. I realized it last December during a lesson about “the attitude of giving”.
Perhaps you already know where to find Acts 20:35 in the gospels, but in case you do not …
“Then He also said to him who invited Him, “When you give a dinner or a supper, do not ask your friends, your brothers, your relatives, nor rich neighbors, lest they also invite you back, and you be repaid. But when you give a feast, invite the poor, the maimed, the lame, the blind. And you will be blessed, because they cannot repay you; for you shall be repaid at the resurrection of the just.”” (Luke 14:12-14 NKJV)