Numbers 15:26

And it shall be forgiven all the congregation of the children
of Israel
Which is repeated for the certainty of it, and for the sake of what follows:

and the stranger that sojourneth among them;
the proselyte of righteousness; so the blessing of pardon, through the propitiatory sacrifice of Christ, comes upon believing Gentiles as well as Jews, ( Romans 4:9 ) ( 1 John 2:2 ) ;

seeing all the people [were] in ignorance;
both the congregation of Israel and the stranger; (See Gill on Numbers 15:25).