This text comes from A First Series of Hymns and Songs, a historical songbook transcribed on Wikisource and reproduced from the pinned revision linked below.
To ancient Milan's city fair,
Where holy Ambrose dwelt,
A woman came in deepest wo,
And at his feet she knelt:
"Father, I weep both day and night,
My very heart is riv'n,
My unbelieving son is still
By pride and passion driven.
He wanders to and fro on earth,
His spirit seeking rest;
And finding none, he drains a cup
By God and man unblest.
His voice, O Father, still upholds
Each impious sect in turn,
And men from his impassion'd words
Pernicious errors learn."
"Rise, daughter, rise," the saint replied,
"Take courage from thy fears;
The child will not be lost for whom
A mother sheds such tears."
For Austin unbaptized it was
That weeping mother pray'd,
And on Saint Austin's breast at last
Her dying head was laid.