Psalms 21:4

He asked life of thee, [and] thou gavest [it] him
Both for himself, as man, when he was about to die, that he might be raised to life again, which was granted him; and for his people, that they might live spiritually and eternally, and accordingly life is given to him for them; and he has power to give it to as many as the Father has given him, ( John 17:2 ) ;

[even] length of days for ever and ever;
the life he has for himself as man is what will ever continue; he will die no more, death will have no more dominion over him; he will live for evermore, and that to make intercession for his members, ( Romans 6:9 Romans 6:16 ) ( Revelation 1:18 ) ( Hebrews 7:25 ) ; and the life which is granted them at his request is an everlasting one, both as to body and soul; for though they die as other men, they shall live again in the resurrection of the just, and never die more, but shall be like the angels in heaven; and as for the second death, that shall not harm them, nor have any power over them; they will live and reign with Christ for ever.