John 20:17

Jesus saith unto her, touch me not
Not that his body was an aerial one, or a mere "phantom", which could not be touched; the prohibition itself shows the contrary; and besides, Christ's body was afterwards presented to Thomas, to be touched by him, and to be handled by all the disciples; and his feet were held by the women, which is what Mary would have now done: upon the discovery of him, she threw herself at his feet, and was going to embrace and kiss them, to testify her affection and joy, when she is forbid; not as unworthy of the favour, because she sought him among the dead, for which the angels reproved her and the rest; but either because he was not to be conversed with, as before his death, his body being raised immortal and glorious; or rather, because he had an errand to send her on to his disciples, which required haste; nor need she stay now to show her respect to him, since she would have opportunity enough to do that, before his ascension; which though it was to be quickly, yet not directly and immediately; and this seems to be the sense of our Lord's reason:

for I am not yet ascended to my Father;
nor shall I immediately go to him; I shall make some stay upon earth; as he did, forty days before his ascension; when he intimates, she might see him again, and familiarly converse with him; at present he would have her stay no longer with him:

but go to my brethren;
this he says, to show that their carriage to him, being denied by one of them, and forsaken by them all, and the glory he was raised unto, as all this made no alteration in their relation to him, so neither in his affection to them: Mary was a very proper person to be sent unto them, since she had lately been with them, and knew where they were all assembled together:

and say unto them;
as from himself, representing him as it were:

I ascend unto my Father and your Father, and to my God and your God;
God was his Father, not by creation, as he is to angels, and the souls of men, and therefore is called the Father of spirits; nor by adoption, as he is to the saints; nor with respect to the incarnation of Christ, for, as man, he had no father; or with regard to his office as Mediator, for as such he was a servant, and not a Son; but he was his Father by nature, or with regard to his divine person, being begotten of him, and so his own proper Son, and he his own proper Father; which hold forth the natural and eternal sonship of Christ, his equality with him, and distinction from him: and God was the Father of his disciples by adopting grace, in virtue of the covenant of grace made with Christ, and through their spiritual relation to him, as the natural and eternal Son of God: God the Father is the God of Christ as man, who prepared, formed, anointed, supported, and glorified his human nature; and in which nature, he prayed to him as his God, believed in him, loved and obeyed him as such; wherefore the Jew ^F15 very wrongly infers from hence, that he is not God, because the God of Israel was his God; since this is spoken of him as he is man: and he was the God of his disciples, in and by the covenant of grace made with Christ, as their head and representative; so that their interest in God, as their covenant God and Father, was founded upon his being the God and Father of Christ, and their relation to, and concern with him; and which therefore must be firm and lasting, and will hold as long as God is the God and Father of Christ: this was good news to be brought to his disciples; which, as it carried the strongest marks of affection, and expressions of nearness of relation; and implied, that he was now risen from the dead; so it signified, that he should ascend to God, who stood in the same relation to them, as to him; when he should use all his interest and influence on their behalf, whilst they were on earth; and when the proper time was come for a remove, that they might be with him, and with his God and Father and theirs, where they would be to all eternity.