I believe that the verse I have quoted here (Jude 1:24) is qualified by Hebrews 2:18.And also, God is able to keep us from falling and to present us faultless before His presence with exceeding joy.
Heb 2:18, For in that he himself hath suffered being tempted, he is able to succour them that are tempted.
Therefore, when it says that He is able to keep us from falling, the topical context speaks of the fact that He is able to help us not to fall into sin, that is, give in to temptation.
And therefore the topical context does not allow for the interpretation that He is able to keep us from falling away; apart from Him being able to keep us from falling into sin / temptation.