John Gill Commentary Luke 20:36

"for neither can they die any more: for they are equal unto the angels; and are sons of God, being sons of the resurrection." — Luke 20:36 (ASV)

Neither can they die any more
Therefore there will be no need of marrying to procreate children, to keep up a succession of men, any more than there is among the angels: for they are equal unto the angels ;
in spirituality, purity and immortality; (See Gill on Matthew 22:30)

and are the children of God :
as they are now by adopting grace; but, as yet, it does not appear as it will then, what they are and will be:

being the children of the resurrection ;
as Christ was declared to be the son of God by his resurrection, so will they appear to be the children of God by their resurrection to eternal life; for though others will rise, yet not to everlasting life, and thus appearing to be children of God, they will also be heirs of God, and enjoy the inheritance, which they will always live to possess in their persons; and therefore the case being different with them from the children of the world, they will not marry, nor be given in marriage, as they are.