But first, understand, that God, does not Need ... God, Gives ... For one who needs is surely, not God !
Regarding your question about our Sacrificings ... It depends, on What, and Why, do we Sacrifice ... and for whom do we sacrifice.
If our Sacrifice or Sacrifices are for this world ... meaning, for worldly gains ... The Just Lord also Rewards our worldly efforts ... but Rewards us here, in this material world ... with whatever, we have Sacrificed for.
This means, that those, sacrificing for this world's Material Wealths and Possessions, essentially do not Believe in God, because, to Believe is to live and die for what we Believe In... and they live and die, for this world ... not God.
Because they deny the Hereafter ...
I, am a Muslim, I Believe in Allah and His Created ... Hereafter ... I know, what I do not "get" here, as The Lord's Reward, for my Efforts ... due to the "worldly ones" machinations ... Shall be Justly Rewarded by Allah, in the Hereafter ... In, that Allah's Rewarding Is, Boundless.