16 “The Lord is near unto all that call upon Him”. Where then is that, “Then shall they call upon Me, and I will not hear them”? See then what follows: “all who call upon Him in truth.” For many call upon Him, but not in truth. They seek something else from Him, but seek not Himself. Why do you love God? “Because He has made me whole.” That is clear: it was He that made you so. For from none else comes health, save Him. “Because He gave me,” says another, “a rich wife, whereas I before had nothing, and one that obeys me.” This too He gave: you say true. “He gave me,” says another, “sons many and good, He gave me a household, He gave me all good things.” Do you love Him for this?...Therefore if God is good, who has given you what you have, how much more blessed will you be when He has given you Himself! You have desired all these things of Him: I beseech you desire of Him Himself also. For these things are not truly sweeter than He is, nor in any way are they to be compared to Him. He then who preferrs God Himself to all the things which he has received, whereat he rejoices, to the things he has received, he “calls upon God in truth.”...
Source: The Enarrations, or Expositions, on the Psalms (New Advent)