Perkins and OT Types

Here's a fascinating, and I would say typically puritan (pardon the pun) use of two Old Testament types for a New Testament concept, from a discussion by William Perkins on the combat between the flesh and the Spirit in the Christian (Galatians 5:17).

I'm interested to hear some feedback – do you think Perkins was over-reaching in using these or not?:

"... hereby we are taught to be watchfull in prayer. Watch & pray (saith Christ, &c. for the spirit is ready but the flesh is weak.) Rebecca, when 2. twins strove in her wombe was troubled & said, why am I so? wherefore she went to ask the Lord, namely for some prophet. So when we feele this inward fight, the best thing is to have recourse to God by prayer, and to his word, that the spirit may be strengthened against the flesh.

As the children of Israel by compassing the city Jerico 7. daies, and by sounding rammes hornes overturned the walles thereof: so by serious invocation of Gods name the spirite is confirmed, and the turrets and towres of the rebellious flesh battered."

- from Two Treatises, I. Of the nature and practise of repentance. II. Of the combat of the flesh and the spirit (1593), 95-96.

I haven't decided whether these are legitimate types for the combat of the flesh and the Spirit, but I do covet the kind of familiarity with Scripture that can recognize such correlations.