CC Madhya 22.67

śāstra-yukti nāhi jāne dṛḍha, śraddhāvān
‘madhyama-adhikārī’ sei mahā-bhāgyavān
Synonyms: 
śāstra-yukti — logical arguments on the basis of the revealed scripture; nāhi — not; jāne — knows; dṛḍha — firmly; śraddhāvān — faithful; madhyama-adhikārī — second-class devotee; sei — he; mahā-bhāgyavān — very fortunate.
Translation: 
“One who is not very expert in argument and logic based on the revealed scriptures but who has firm faith is considered a second-class devotee. He also must be considered most fortunate.