Strength or weakness?

In the context of human strength or weakness, how do you unpack Isaiah 40:6-8? Step 3 of LifeWay lesson “Take Comfort in God’s Strength” posits “grass and flowers” as “human glory”, and then concludes we need to acknowledge our weakness to experience God (see LifeWay Leader commentary (p. 87)). When it comes to avoiding sin, this weakness could be mistaken as “I just can’t help myself".

As a means of redemption, Peter (1 Peter 1:17-25) thought of grass and flowers as human strength, which withers and falls. We have no power to save ourselves, and Troy Bush states that we wrongly draw comfort from our own means instead of depending on God’s enduring power.

No doubt the Bible teaches, “power is found in weakness,” according to Alistair Begg. But we don’t want to reinforce the notion that this weakness is an excuse to sin, i.e. “I’m only human.”