All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
If a Muslim helps another Muslim financially in order to perform Hajj, then it is hoped that Allaah will grant the latter the reward of Hajj, because whoever guides people to do good, he gets the same reward as the person who performs that good deed as confirmed by the Prophet . This help is also included in helping in righteousness and piety, as Allaah Says (what means): {Help you one another in virtue, righteousness and piety but do not help one another in sin and transgression. And fear Allaah; indeed, Allaah is severe in penalty.}[Quran 5:2]
Similarly, if a person is unable to perform Hajj due to a sickness from which he is not expected to recover or due to being advanced in age, and another person performs Hajj on his behalf, then the former [the person who is unable] will get the reward of performing Hajj, Allaah willing, and he becomes acquitted from the obligation of Hajj.
For more benefit, please refer to Fatwa 88989.