score:6
From experience, it is a relatively common teaching in Pentecostal and Charismatic circles that one of the benefits of praying in tongues is that Satan can't understand it (and can't stand it!). As well as the verses you've cited, this doctrine is also supported by Romans 8:26-27 -
26 Likewise the Spirit helps us in our weakness. For we do not know what to pray for as we ought, but the Spirit himself intercedes for us with groanings too deep for words. 27 And he who searches hearts knows what is the mind of the Spirit, because the Spirit intercedes for the saints according to the will of God. (ESV)
For those unfamiliar with Pentecostal/Charismatic doctrine, where the bible talks about 'praying in the Spirit' it is taken as synonymous with praying in tongues (cf. 1 Cor 14:14-15)