In Mark 4:40 and Matthew 8:26 fear/deilos is compared to faith:
"He said to them, 'Why are you so afraid? Have you still no faith'" Mark 8:26 ESV
"And he said to them, 'Why are you afraid, O you of little faith?' Matthew 8:26
In Matthew 8:25 the disciples have enough faith to say to Jesus "Save us , Lord". But not enough faith not to have fears in the first place.
"For whatever does not proceed from faith is sin". Romans 14:23
In 1 John 4:18 fear/phobos [very similar] is seen in relation to love:
"There is no fear in love, but perfect love casts out fear. For fear has to do with punishment, and whoever fears has not been perfected in love."1 John 4:18 [perfect-teteleiotai]
Sin is punished on "the day of judgement" 1 John 4:17. Something to be feared.
Perfect love. Love reaches a teleological end in this world when it drives out fear. It does so by replacing it with:
"the love that God has for us".1 John 4:16