Passage
For if any man think himself to be some thing, whereas he is nothing, he deceiveth himself.
For if any man think himself to be some thing, whereas he is nothing, he deceiveth himself.
Galatians 6:1 Brethren, and if a man be overtaken in any fault, you, who are spiritual, instruct such a one in the spirit of meekness, considering thyself, lest thou also be tempted.
Galatians 6:2 Bear ye one another's burdens: and so you shall fulfil the law of Christ.
Galatians 6:3 For if any man think himself to be some thing, whereas he is nothing, he deceiveth himself.
Galatians 6:4 But let every one prove his own work: and so he shall have glory in himself only and not in another.
Galatians 6:5 For every one shall bear his own burden.
The verse centers on "think", "himself", "some", "whereas", "nothing", and "deceiveth". It is saying that the verse draws attention to "think" and "himself", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 2's "Bear ye one another's burdens and so..." into verse 4's "But let every one prove his own...", so "think" and "himself" belong inside that flow. In Galatians context, the local focus is Christ, faith, and discipleship.
A plain takeaway is to answer the verse's own emphasis on "think" and "himself" with trust shaped by these words, not by a vague optimism outside the passage.