This verb means to watch over carefully, keep safe, or treasure something valuable. Luke uses it for Mary 'treasuring' all the words about Jesus in her heart (2:51), while Acts employs it for the apostolic decree that Gentile believers should keep themselves from certain practices (15:29). The prefix 'dia-' suggests thoroughness—keeping through and through, maintaining carefully over time. The term implies both protective custody and faithful observance. Spanish 'guardaba' (was keeping/treasuring) and French 'garder' (keep/guard) capture this sense of careful preservation, whether of memories or commands. The word suggests vigilant, ongoing care rather than casual retention.