It is possible that the point of the metaphor is vulnerability: The psalmist, who is threatened by his enemies, feels as vulnerable as a straying, lost sheep. This would not suggest, however, that he has wandered from God’s path (see the second half of the verse, as well as v. 110...
Preparing to preach on Psalm 127 (128), and having explained the spiritual interpretation of the Psalm and the unity of Christ and the church, Augustine reminds the flock that the love described by John banishes fear (En. 127, 7; Augustinus 2001, CSEL 95/3, pp. 213–14, Gori). The ...