Jesus says this to help us grasp the marvelous, obliging, and almost overwhelming generosity and magnanimity of God's approach toward His creation. He acts this way despite all that we have thoughtlessly and self-centeredly done against Him personally and His creation, which certainly includes other people both converted and unconverted. Regardless, He still gives and gives some more. Why? Because this is the way that He is by nature, setting us an example of what He wants us to become in our natures too.
Do not be misled, though. He is not a thoughtless, wealthy, spendthrift sap. He does all this giving with purposeful wisdom, and especially so with His children that He is now preparing for His Family Kingdom.
When dealing with His children, His giving nature does not change. It is, however, more directed and focused on their preparation for their future in His Kingdom. Yes, He directly tests us, but because we are the apple of His eye, He provides us with the comfort and encouragement of I Corinthians 10:13:
No temptation has overtaken you except such as is common to man; but God is faithful, who will not allow you to be tempted beyond what you are able, but with the temptation will also make the way of escape, that you may be able to bear it.
Thus, we are given assurance that even in the midst of the difficulties necessary for our preparation to inherit the Kingdom as co-heirs with Christ, He will generously supply our needs.