Infallible denotes the quality of never deceiving or misleading and so means wholly trustworthy and reliable; inerrant means wholly true. Scripture is termed infallible and inerrant to express the conviction that all its teaching is the utterance of God who cannot lie, whose word, once spoken, abides for ever, and that therefore it may be trusted implicitly.
J. I. PackerThe meaning of "He will give us all things" can be put thus: one day we will see that nothing - literally nothing - which could have increased our eternal happiness has been denied us, and that nothing - literally nothing - that could have reduced that happiness has been left with us.
J. I. Packer