To get a revision from a Repository object:

$revision = $repository->getRevision('master@{2 days ago}');

Getting the log

You can access a Log object starting from a revision using the getLog method. This method takes two parameters: offset and limit:

// Returns 100 lasts commits
$log = $revision->getLog(null, 100);

Resolve a revision

To resolve a revision to a commit:

$commit = $revision->getCommit();