The Sarum Rite, the principal Latin liturgy in medieval England, did not refer to the Ascension in the collect for the following Sunday.  Cranmer and his fellow compilers decided to go in a different direction. Because of their emphasis on our need for the Holy Spirit in the Christian life, they repurposed an antiphon from Vespers for Ascension Day instead.  The ancient text read:

O Lord, King of glory, Lord of virtues, who today didst ascend in triumph above all heavens, do not leave us orphans, but send upon us the promise of the Father, even the Spirit of Truth.

Copyright 2021 John Ashley Null; all rights reserved; used by permission for educational purposes