And let it be, when these signs are come unto thee, that thou do as occasion serve thee; for God is with thee.

When therefore these signs shall happen to thee, do whatsoever thy hand shall find, for the Lord is with thee.

And it shall be, when these signs shall come to thee, thou shalt do as thy hand shall find; for God is with thee.

and it hath been, when these signs come to thee, do for thyself as thy hand findeth, for God is with thee.

And when these signs come to you, see that you take the chance which is offered you; for God is with you.

Therefore, when these signs will have happened to you, do whatever your hand will find, for the Lord is with you.

Thou do as occasion serve thee - After God has shown thee all these signs that thou art under his especial guidance, fear not to undertake any thing that belongs to thy office, for God is with thee.
What a number of circumstances thus precisely foretold! Does not this prove that Samuel was under the continual inspiration of the Almighty?

And let it be, when these signs are come unto thee,.... And are all fulfilled, especially the last:
that thou do as occasion shall serve thee: as his circumstances would require, and as he in his great wisdom and prudence, with which he should now be furnished, would see necessary to prepare for his taking upon him the kingdom he was anointed to, and would be in a little time openly chosen to, and invested with. Some understand this of royal ornaments befitting a king, or of preparing arms for the defence of the kingdom:
for God is with thee; or the Word of the Lord is thy help, as the Targum, and therefore he need not fear engaging in any enterprise that might be for the glory of God, and good of the kingdom.

"When these signs are come unto thee (the Kethibh תבאינה is to be read תּבאינה, as in Psalm 45:16 and Esther 4:4; and the Keri תּבאנה is a needless emendation), do to thee what thy hand findeth, i.e., act according to the circumstances (for this formula, see Judges 9:33); for God will be with thee." The occurrence of the signs mentioned was to assure him of the certainty that God would assist him in all that he undertook as king. The first opportunity for action was afforded him by the Ammonite Nahash, who besieged Jabesh-gilead (1-Samuel 11:1-15).

Thou do - Hebrews. do what they hand findeth to do; that is, as thou shalt have a call and opportunity. He doth not intend that he should take the kingly government upon him, before his call to it was owned by the people, but that he should dispose his mind to a readiness of undertaking any public service when he should be called to his office.