Is it permissible to sell DVDs containing religious lessons recorded from the internet or satellite channels, with the aim of spreading knowledge and earning a modest income?

We do not know of any impediment to publishing religious lectures. Rather, it is presumed that their owners would be pleased with their publication, as it increases their good deeds. Most satellite channels make an archive of their programs available for download, which implies no objection. Publishing these programs is considered promotion for the channel, especially if it does not explicitly state the preservation of copyrights. Therefore, there is no blame on whoever does so.